Increased Photocatalytic Activity of Post Synthetically Modified Coordination Polymer Derived from Bis-pyridyldiamide

Article abstract of DOI:10.1002/ejic.202000450

A one-dimensional looped chain coordination polymer (CP1) is synthesized by the reaction of Co^II with N¹,N³-di(pyridine-4-yl)isophthalamide. Transmetalation reaction of CP1 with Cu^II showed single-crystal-to-sin

Full text of DOI:10.1002/ejic.202000450

European Journal of Inorganic Chemistry
Accepted Article
Title: Increased Photocatalytic Activity of Post Synthetically Modified
Coordination Polymer derived from bis-Pyridyldiamide
Authors: Moyna Das, Sadhika Khullar, and Madhushree Sarkar
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: Eur. J. Inorg. Chem. 10.1002/ejic.202000450
Link to VoR: https://doi.org/10.1002/ejic.202000450
0
1/2020

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Increased Photocatalytic Activity of Post Synthetically Modified
Coordination Polymer derived from bis-Pyridyldiamide
[
a]
[b]
[a]
Moyna Das, Sadhika Khullar, and Madhushree Sarkar*
[
a]
M. Das, Dr. M. Sarkar
Department of Chemistry, Birla Institute of Technology and Science, Pilani,
Pilani Campus, Rajasthan, India.
Fax: +91-1596-244183
Tel: +91-1596-255679
E-mail: msarkar@pilani.bits-pilani.ac.in
https://www.bits-pilani.ac.in/pilani/madhushreesarkar/profile
Dr. S. Khullar
[
b]
Department of Chemistry, Dr B R Ambedkar National Institute of Technology Jalandhar,
Jalandhar, Punjab 144011, India.
E-mail: khullars@nitj.ac.in
Supporting information for this article is given via a link at the end of the document.
Abstract: A one-dimensional looped chain coordination polymer
alkyl/aryl spacer, involve a combination of amide functionality for
hydrogen bond interactions and pyridyl groups for coordination
bond interactions.
1
3
(CP1) is synthesized by the reaction of Co(II) with N ,N -di(pyridine-
4-yl)isophthalamide. Transmetalation reaction of CP1 with Cu(II)
showed single-crystal-to-single-crystal (SC-SC) transformation to
form CP2, which is also a 1D looped chain. Both CP1 and CP2
showed the presence of DMF as guest molecules near the loops of
the 1D chains. CP1 and CP2 were found to have band gaps of 2.41
eV and 1.30 eV, respectively, which were calculated by Tauc plot. The
difference observed in the optical band gaps of CP1 and CP2 is
reflected in photocatalytic dye degradation studies. It was observed
that CP2 showed much greater efficiency in degrading the dyes
(Methylene blue, Methyl orange and Rhodamine B) as compared to
that of CP1. The polar nature of the loops of the chains in CP1 and
CP2 due to the presence of DMF was exploited to study the
adsorption and desorption of I
2 2
. Adsorption of I in CP1 and CP2 was
Scheme 1. Pyridyl based exo bidentate ligands equipped with groups for
coordinate bond as well as hydrogen bond interactions
−5
found to follow first order kinetics with a rate constant of 8.32  10
−1
−5 −1
s
for CP1 and 9.71  10 s for CP2. Guest inclusion reaction was
performed to incorporate benzotriazole in the CP1. Impedance
measurements showed a higher conductivity in the benzotriazole
incorporated CP1.
Dastidar and coworkers have synthesized metal-organic
frameworks (MOFs) with 2b and 3b wherein they analyzed the
structural diversities of the MOFs resulting due to the positional
isomerism of ligands and also performed counter anion exchange
studies of the MOFs.[11] They have also reported a 2D corrugated
sheet[12] with 2b, metallogels with 2b and 2c, and a borromean
weave CP[14] with 2c. Among various important applications, they
have shown the isolation of fluoride ion using a 3D non-
interpenetrated CP of 2b and 2c.[15] Mukherjee and coworkers
have explored coordination driven self-assembly by using 2b/3b
Introduction
[13]
Crystal engineering of metal-organic frameworks (MOF) or
coordination polymers (CPs) has shown multidimensional
applications in the areas of gas storage,[1] catalysis,[2]
magnetism,[ luminescence materials, electrical conductivity,[5]
biological applications[6] and so on. Design strategies require the
synthesis of ligands or linkers which can enable the extension of
CPs or MOFs into higher dimensionality not only by utilizing
coordinate bond interactions but also by involving non-covalent
interactions such as hydrogen bond interactions.[7] Overall
geometry of a CP or MOF depends on many factors which include
solvent, temperature, pH etc.[8] Design of CPs using ligands
equipped with hydrogen bond functionalities can lead to the
formation of networks which can recognize counter anions and
various guest molecules via hydrogen bond interactions. One of
the well-known hydrogen bond functionality is the amide group[9]
which has been exploited widely in anion recognition[10] and
separation. Pyridyl based exo bidentate ligands (Scheme 1),
where pyridyl groups are separated by amide moieties and an
3]
[4]
[16]
ligands, which resulted in the formation of nanoscopic prism,
molecular prism,[
17]
Pt(II) based metallomacrocycles,
[18]
Pd(II)
based molecular rectangles,[19]
octanuclear Pt(II) based
tetragonal prism,[20] hexanuclear Pt(II) based nanoscopic
cages,[21] Pt(II) based macrocycles and explored their various
applications such as sensing of nitroaromatics etc. Gong et al.
have prepared CPs using 3b, which showed reversible color
change by desolvation and solvation.[23] Han et al. have reported
CPs by using dicarboxylic acids along with 3b and observed the
effect of temperature on the conformations of 3b in the CPs.[
Gong et al. have also designed MOF based on mok nets topology
where dicarboxylic acid was used as a co-ligand.[25] Further they
have exploited the photo-luminescence properties of the CPs
from 3b and 3c along with various dicarboxylic linker.[ Gong et
al. have also synthesized a supercapacitor material by using 3b
[22]
24]
26]
1
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
and diacid ligands, wherein, 3b formed 1D looped chain with the
metal centre which is further connected by a diacid linker to form
a 3D microporous architecture network.[27] Puddephatt and
coworkers have synthesized several palladium lantern[28] type
complexes and laminated sheet-like[29] structure of CPs by using
developed a graphene based photocatalyst with 3D porous
carbon nanotubes and observed its effectiveness in degrading
[52]
2
rhodamine B (RB) under UV light irradiation. A TiO supported
graphene composite is reported by Xijiang Han group which acted
as a photocatalyst for methylene blue (MB) degradation under UV
light.[53] Yi-Jun Xu group has been involved in developing efficient
photocatalysts for degrading RB using graphene modification
through tuning[54] and doping[55]. An elaborate review by Yi-Jun Xu
group showcased the developments and drawbacks of
photocatalyst.[56]
3
b and 2b ligands for application in host-guest chemistry. Biradha
and coworkers have synthesized CPs of varied networks and
geometries and elaborately studied their assembling via hydrogen
bond interactions.[30] They have reported CPs of 2c and 3c with
guest molecules such as benzonitrile,[31] nitrobenzene[32] and also
without guest molecules.[33] Feng Luo group has exploited 2b, 2c
and 3b in synthesizing CPs and studied their photo-switching
behavior,[34] xylene isomer sensing,[35] phosphor material[36] and
photoluminescence[37]. They have also shown a solvent induced
change in network geometry of a CP of 2b.[38]
Last two decades has seen a considerable rise in the research
involving the use of MOFs/CPs in purification of water using
photocatalytic technology.[57] Presence of porosity in MOFs/CPs
is one of the most advantageous property which makes them a
suitable candidate for photocatalysis. In photocatalytic
degradation of dyes, previous studies mainly involved the usage
of 60% of UV light and 30% of visible light. Now researchers are
more focused in utilizing 10% of solar light as natural energy
sources.[ Proper selection of metal ions along with N and O
containing conjugated ligands are required to tailor made
CPs/MOFs, which can result in enhanced photocatalytic
efficiency. Porosity in CPs/MOFs will be effective in providing
Post-synthetic structural modulation in CPs/MOFs can be
triggered by various external stimulus such as ion exchange,
thermal effect, solvent effect, light induced, mechanochemical
forces and so on. Post-synthetic modification of CPs can be
utilized efficiently to tailor made the CPs to get desired properties
which may not be possible via direct synthesis.[39] Kim and
58]
coworkers
have
reported
single-crystal-to-single-crystal
transformation of
a
Cd(II) based CP of 5,5,10,10,15,15-
2
large surface area to incorporate O /OH radical for degrading the
Hexaethyltruxene-2,7,12-tricarboxylic acid wherein the Cd(II)
centres were replaced by Pb(II) and 98% of the transformation
was observed within 2 h.[40] They have also synthesized Co/Ni/Cu
frameworks via metal metathesis of Mn(II) MOF of
dye. There are many reports on photocatalysis involving Cu(II),
Zn(II) and Cd(II) MOFs using ligands such as imidazole[59],
pyrazole[60] etc. Mahata et al. has synthesized Ni(II) and Co(II)
CPs of 4,4-oxybisbenzoate and 4,4-bipyridine ligands wherein
the CPs were observed to degrade the Rhodamine B (RB),
Methylene blue (MB) and Remazol Brilliant Blue R (RBBR).[
Li−Ya Wang group has synthesized a 2D Zn(II)-MOF based on 4-
(pyridyli-4-yl) phthalic acid which showed photocatalysis in
degrading RB and methyl orange (MO) up to 98.5% and 83.8%
5
,5,10,10,15,15-Hexamethyltruxene-2,7,12-tricarboxylic acid and
61]
observed metal specific properties related to hydrogen adsorption
and magnetization.[41] Tian et al. have prepared an anionic MOF
using
tetrakis-[4-(carboxyphenyl)oxamethyl]methane
and
observed SC-SC transformation leading to the selectively capture
Co2+ and Ni2+ among various transition metals.[42] Bharadwaj and
coworkers have reported SC-SC transformation wherein Zn(II) in
[62]
efficiency respectively in absence of any photosensitizer.
Guang Yang group has reported efficient photocatalysis of MB,
RB and MO by using Cu-triazolate MOF.[ One of the major
challenges in using MOFs/CPs as photocatalyst is its stability in
aqueous medium. Bedia and coworkers have done an extensive
review on the challenges related to using MOFs/CPs as
photocatalyst; which include stability of MOFs/CPs in aqueous
medium under visible light, loading amount required for catalysis,
recyclability and rate of degradation of dyes.[64] MIL-53 Fe(III)
(MIL: Material Institute Lavoisier) is one of the MOF examples
which was studied as photocatalyst for dye degradation in water
system.[65] It was also reported that other MIL MOFs, UiO-66
(University of Oslo) and ZIFs (Zeolitic imidazolate frameworks)
series acted as efficient water-stable photocatalyst. A recent
review by Qi Wang and Shengqian Ma showed an extensive
coverage on the developments of MOF based visible light
photocatalyst.[66]
63]
the
tetracarboxylic acid was replaced by Cu(II) and observed an
enhanced CO adsorption property in the Cu(II) MOF than the
MOF
of
2-amino-[1,13,1terphenyl]-3,3,5,5-
2
presynthesized MOF.[43] Zhou and coworkers have post
synthetically performed the synthesis of MOF of earlier transition
metals such as Cr (II) and Fe (II) where a step by step SC-SC
transformation of Mg(II) MOF of 2,3,5,6-tetramethyl-
[
1,1:4,1:4,1-quaterphenyl]-3,3,5,5-tetracarboxylic
acid
[44]
resulted in the corresponding Cr(II) and Fe(II) MOFs. Tomar
and coworkers have shown an improved catalytic activity of a CP
of Zn(II) using 5-(benzylamino)isophthalic acid after post-
synthetic replacement of Zn(II) to Cu(II). Das and coworkers
have reported a quantitative transmetalation of Zn(II) to Cu(II) by
employing bis-pyrazolylpyridine carboxylate ligand.[46] Our group
has previously reported a transmetalation reaction in a Cd(II) CP
of N ,N -di(pyridin3-yl)adipamide, where Cd(II) centres were
completely replaced by Cu(II) ions without altering the geometry
of the network.[47]
[45]
1
6
High-temperature
sustainability,
tunable
porosity,
and
dimensionality associated with CPs/MOFs make them favorable
candidates in the applications involved in charge transport[
67]
Dye effluents are the result of various industrial sources like paper, Kitagawa and coworkers have reported the encapsulation of
rubber, textile, printing, cosmetics, leather and plastics.[48] Many
such non-biodegradable dyes are carcinogenic and also have
harmful effects on the aquatic environment. Several
photocatalysts has been used in dye degradation such as
graphene based photocatalyst[49], metal oxide photocatalyst[50]
and CPs/MOFs[51] based photocatalyst. X. S. Zhao group has
proton carrier imidazole molecule into a porous CP and observed
−5
−1
[68]
an increase in the conductivity to 2.2  10 S cm at 120 °C.
Fuma et al. have reported an increase in conductivity to 1.4  10
S cm due to the rehydration of water molecules in the interstitial
site of
CP.[69] You et al. synthesized an MOF,
NH Br@HKUST−1 by soaking HKUST-1, which is a MOF built
−3
−1
a
4
2
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
from Cu-paddle wheel nodes with 1,3,5-benzene-tricarboxylate
leading to possibilities of varied geometries and properties of CPs.
An exo bidentate ‘V’ shaped rigid ligand 3b is used in the current
study specifically to ascertain the possibility of generating porous
networks. CP1 and CP2 showed some marked property
difference due to the effect of replacing Co(II) with Cu(II).
struts, in a saturated ethanolic solution of NH
increase in conductivity by three/four orders of magnitude in
NH
Br@HKUST-1 than that in HKUST-1.[70] Hiroshi Kitagawa
4
Br and observed an
4
group has synthesized a porous coordination polymer by
introducing electron donors and acceptors as building units, which
showed high electrical conductivity (6  10−4 S cm ). Himoto et
al. have synthesized several semiconducting CP using mixed
valance metal ions and dithiocarbamate ligands.[72] Banerjee and
coworkers have reported first proton conducting CP based on
−1 [71]
Results and Discussion
1
3
The
reaction
of
Co(SCN)
2
with
N ,N -di(pyridine-4-
−5
polyoxometalate and achieved a conductivity of 2.2  10
cm .
S
yl)isophthalamide (3b) has resulted in the formation of CP1. Post-
synthetic modification of CP1, wherein the transmetalation
reaction of CP1 with Cu(II) was performed, resulted in CP2
(Scheme 2). Crystal structure analysis of CP1 and CP2 were done
in order to study the impact of changing the metal centre from
Co(II) to Cu(II) on the CPs. Crystal data and structure refinements
of CP1 and CP2 are summarized in table 1. Although substantial
changes were not observed in the overall network geometry of
CP1 and CP2, but the differences were mainly present in terms
of coordination environment of the metal centre and conformation
of 3b.
−1 [73]
1
3
In the current work, we have used N ,N -di(pyridine-4-
yl)isophthalamide, 3b, to synthesize a Co(II) based coordination
polymer, CP1. Transmetalation reaction of CP1 with Cu(II)
resulted in SC-SC transformation to form CP2. The ligand 3b has
a 1,3-disubstituted aromatic group in the spacer along with two
amide groups (Scheme 1). Presence of 1,3-disubstituted aromatic
moiety has resulted in ‘V’ shaped geometry to the ligand 3b while
the amide groups being important hydrogen bond functionalities,
will be actively involved in diverse non covalent interactions
Scheme 2. Synthesis of CP1 and CP2: Analysis of adsorption-desorption of iodine, solvochromism, photocatalytic dye degradation and impedance measurement
3
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Transmetalation reaction was monitored by atomic absorption
spectroscopic analysis (AAS) and also by energy dispersive X-ray
spectroscopy (EDX), wherein it was observed that more than 95%
of the reaction was completed within 6 h duration (Figure 1 and
Figure S1). CP1 and CP2 were exploited as photocatalyst for
degradation of organic dyes and kinetic studies of the
photocatalysis were done. The presence of loops in the networks
of CP1 and CP2 encouraged us to observe the properties
associated with adsorption and desorption of iodine. Both CP1
and CP2 were able to incorporate iodine and resulted in iodine
moieties satisfy the other four coordination sites. [Bond length:
Co-N(3b) 2.158 Å, 2.185 Å; Co-NCS 2.095 Å; Bond angle SCN-
Co-N(3b): 87.54°, 89.52°, 89.79°, 93.15°] (Figure 2a). ORTEP of
CP1 is shown in figure S2. In the crystal structure, three DMF
molecules are found per Co(II). The ligand 3b has three aromatic
moieties and two amide groups, which give an overall rigidity to
the molecule. The possible structural modulations in 3b include
the bond rotation which can only result in change in the interplanar
angles between the aromatic planes and amidic planes. In order
to analyze the geometry of 3b in CP1, molecule of 3b can be
segregated into five different planes (Figure 2b). The interplanar
angles between these five planes are listed in table 2. An
important observation regarding the geometry of 3b in CP1 is that
the NH of both the amidic groups are pointing in the same
direction and the interplanar angle between the two amidic planes
2 2
adsorbed CPs, I @CP1 and I @CP2 (Scheme 2). Further
removing DMF from the networks of CP1 and CP2 resulted in
CP1* and CP2*, both of which showed significant color changes
reflecting the changes in the coordination environment of metal
centres on removing DMF (Scheme 2).
(
Plane D and Plane E) is 59.09°. This results in the attainment of
Table 1. Crystal structure data and refinement parameters for CP1 and CP2.a
a ‘V’ shaped geometry of 3b in CP1.
CP1
CP2
Chemical formula
Formula weight
C
47
H
49Co N13
O
7
S
2
50 8 2
C H56CuN14O S
1031.04
296(2)
0.71073
Monoclinic
C2/c
1108.74
296(2)
Temperature (K)
Wavelength (Å)
Crystal system
Space group
a (Å)
0.71073
Monoclinic
1
P2 /c
25.248(8)
14.575(4)
17.180(5)
90
23.287(14)
14.366(9)
17.203(10)
90
b (Å)
c (Å)



(°)
(°)
(°)
118.501(7)
90
106.603(7)
90
Z
4
4
Volume (Å3)
5556.0(3)
1.233
5515.0(6)
1.335
Density (g/cm3)
-
1

(mm )
0.441
0.536
Theta range
1.84° to 25.07°
2148
0.91° to 25.04°
2316
F(000)
Reflections collected
Independent reflection
Reflections with I >2(I)
16260
53538
4930
9719
3809
6546
R
int
0.0437
0.0691
Number of parameters
GO F on F2
333
684
1.107
1.020
Final R
a/wR b
Largest diff. peak and hole
1
a/wR b
2
(all data)
2
(I >2σ(I))
0.0721/0.2403
0.0895/0.2587
0.0493/0.1378
0.0855/0.1704
R
1
-
3
(eÅ )
1.064 and -0.637
0.716 and -0.519
a
b
2
2)2/w(F
2)2]1/2, where w
R
1
= ||F
o
2
| − |F
c
||/|F
o
|. wR
2
= [w(F
o
o
− F
)/3.
c
o
2
2
2
2
=
1/[ (F
o
) + (aP) + bP], P = (F
+ 2F
c
Crystal Structure Analysis of CP1
Figure 1. Transmetalation reaction of CP1 with Cu(II): (a) Reaction kinetics
monitored by EDX (b) Images of single crystal to single crystal transformation
of CP1 to CP2
CP1 has crystallized into Monoclinic C2/c space group in which
each Co(II) centre adopts a distorted octahedral geometry with
-
two axial positions being occupied by the NCS anions, while 3b
4
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Table 2. Orientations of aromatic planes of 3b in CP1 [Planes are labelled in
figure 2b]
Further the interplanar angle between the pyridyl plane (Plane A)
and amidic plane (Plane D) is 4.21° while that between the pyridyl
plane (Plane C) and amidic plane (Plane C) is 16.41°. The
consequence of these interplanar angles between the pyridyl
planes and amidic planes is the absence of self-complementary
amide-to-amide hydrogen bonds between the adjacent 3b units
in CP1, which may be due to the steric hindrance of the pyridyl
groups. The ‘V’ shaped geometry of 3b in CP1 and its further
coordination to the Co(II) has resulted in the formation of 1D
looped chain structure. The metal to metal distance within a loop
is about 14.6 Å while the distance along the shorter axis of the
loop is around 9.2 Å. The NH groups of 3b are pointing towards
the loops while the C=O of 3b are pointing away from the loops.
The DMF molecules present in the network form hydrogen bond
with the NH groups of 3b. For each loop in a chain of 3b, four
DMF molecules form hydrogen bond with four NH moieties
present in the loop, wherein two NH moieties are pointing
upwards while two NH moieties are pointing downwards with
respect to the plane of the loop involving the Co(II) centres (Figure
Planes
Angle
47.56°
39.13°
67.31°
4.21°
Planes
Angle
66.17°
61.36°
23.64°
16.41°
59.09°
Plane A and Plane B
Plane B and Plane C
Plane A and Plane C
Plane A and Plane D
Plane B and Plane D
Plane C and Plane D
Plane A and Plane E
Plane B and Plane E
Plane C and Plane E
Plane D and Plane E
44.06°
Table 3. Interplanar angle between the aromatic planes in two types of 3b units
in CP2 [Planes are labeled in figure 3b]
3
b (Type 1)
3b (Type 2)
Planes
Planes
Angle
Angle
Plane P and Plane Q
Plane Q and Plane R
Plane P and Plane R
Plane P and Plane S
Plane Q and Plane S
Plane R and Plane S
Plane P and Plane T
Plane Q and Plane T
50.73°
44.71°
74.47°
21.55°
30.33°
64.34°
74.60°
44.41°
Plane U and Plane V
Plane V and Plane W
Plane U and Plane W
Plane U and Plane X
Plane V and Plane X
Plane W and Plane X
Plane U and Plane Y
Plane V and Plane Y
54.25°
43.91°
74.48°
18.36°
36.96°
66.29°
65.31°
22.33°
2
c). The packing of 1D looped chains is in offset manner mainly
-
due to the presence of NCS groups, which are coordinating to the
Co(II) and pointing normal to the plane of the loops (Figure 2d).
Crystal Structure Analysis of CP2
The crystal structure analysis of CP2 shows that it has crystalized
Plane R and Plane T
Plane S and Plane T
0.53°
Plane W and Plane Y
Plane X and Plane Y
21.94°
51.89°
in Monoclinic P2
two 3b units, one Cu(II), two SCN and four DMF molecules.
ORTEP of CP2 is shown in Figure S3. The coordination sphere of
1
/c space group and the asymmetric unit contains
64.28°
-
Magnetic Measurement of CP1
-
Cu(II) has one SCN unit coordinated in the axial position along
with four 3b units (Figure 3a). The sixth coordination site in Cu(II)
has SCN ion but its distance is more than the bonding distance
-
Magnetic direct-current (DC) susceptibility measurements in a 1
kOe magnetic field was performed as a function of temperature
[
2
Cu-N(3b): 2.027 Å, 2.039 Å, 2.053 Å, 2.042 Å; Cu-NCS: 2.306 Å,
.833 Å]. The presence of Cu(II) has resulted in an elongated
(
from 1.9 K to 400 K) on pellets of the randomly oriented
polycrystalline sample of CP1. The χ T (χ molar paramagnetic
m
m
geometry due to Jahn Teller distortion (Figure 3c). The distortion
in the coordination sphere of the Cu(II) centre has affected the 3b
conformation as well and has incorporated more asymmetry in the
structure of CP2 compared to that of CP1. Unlike in CP1, CP2
has two 3b units in the asymmetric unit. The geometry of two
types of 3b in CP2 was analyzed more closely by segregating
each 3b units into five planes and observing the interplanar
angles between these planes (Figure 3b, Table 3).
susceptibility) νs T plot of CP1 is shown in Figure 4. At room
1
temperature, the χ
m
T product is 3.22 emu·K·mol− (µeff = 5.08 µB
per Co (II) ion). This value is consistent with the expected value
of 5.3 for Co2+ ions (S = 3/2 with large orbital contribution, so that
−
1
g ≈ 2.5). The χ
m
vs T plot (Figure 4) follows the Curie-Weiss law
−1
with Curie constant of 3.375 emu·K·mol , is in well agreement
with high spin Co (II) ions in an octahedral geometry. CP1 has
shown ferromagnetic interaction which is confirmed from the
positive value of Weiss constant of 4.12.
Both the types of 3b in CP2 attain ‘V’ shaped geometry. Self-
complementary amide to amide hydrogen bond is absent in CP2
and the NH groups of the amides are involved in hydrogen bond
interaction with the DMF molecules (Figure 3d). Also, the
interplanar angle between the amidic plane and the pyridyl plane
Thermal Gravimetric Analysis of CP1 and CP2
For analyzing the thermal stability, 6.26 mg of CP1 was taken and
heated at a rate of 10 °C/min under N
temperature of 700 °C (Figure S4). In the temperature range of
53 °C to 206 °C, one molecule of DMF was lost from CP1 (Actual
2
atmosphere up to a
(
adjacent to the amide) is less (21.55°, 0.53°, 18.36° and 21.94°);
which in turn will hinder the approach of amidic moiety of another
b molecule to form hydrogen bond interactions due to steric
1
3
weight loss = 12.74%; Calculated weight loss for one DMF
molecule = 13.23%) (Figure S5). Another DMF molecule was lost
in the temperature range of 219 °C to 277 °C. The degradation of
CP1 was observed at 313 °C to 446 °C with weight loss 49.78%,
which corresponds to one molecule of 3b ligand (Calculated
weight loss for one 3b molecule = 50.41%). The derivative plot,
i.e. the first derivative of weight % w.r.t time (minute) vs.
temperature (°C), of CP1 and CP1* further clarifies the complete
removal of the DMF molecules from CP1* (Figure S5). TGA of
CP2 and CP2* shows similar behavior (Figure S6 and S7).
reasons. The directionality of the hydrogen bond interaction is
reflected in terms of conformational change of 3b and the shifting
of one of the DMF molecules in loop of the network. Figure 2c and
figure 3d clearly illustrates the effect of conformational change of
3
b in CP1 and CP2 on the positioning of the DMF molecules.
5
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Figure 2. Illustration for crystal structure of CP1: (a) 1D looped chain in CP1, (b) Geometry of 3b in CP1, (c) Hydrogen bond interaction of N-H groups in CP1 with
the DMF molecules (Hydrogen atoms are removed for clarity), (d) Offset packing of the 1D chains (Chains are shown in different colors for clarity)
6
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Figure 3. Illustration for crystal structure of CP2: (a) Asymmetric unit in CP2, (b) Geometry of two types of 3b in CP2, (c) 1D looped chain, (d) Hydrogen bond
interaction of N-H groups in CP2 with the DMF molecules (Hydrogen atoms are removed for clarity), (e) Offset packing of the 1D chains (Chains are shown in
different colors for clarity)
7
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
This resulted in the twisting of the 3b and an overall distortion near
the Co(II) centre. The removal of the DMF molecules may result
in relaxing the 3b molecules thereby might be effective in reducing
the distortion.
Figure 4. Molar magnetic susceptibility of CP1 per formula unit: χ
of CP1 (Magnetic field at 1000 Oe)
m
T vs T plot
Solid State UV-Visible Absorption Spectra Studies
Solid-state UV-Visible absorption spectra of 3b, CP1 and CP2
were recorded by mixing 5 mg of a compound (3b/CP1/CP2) with
5
00 mg of BaSO
absorption maxima at 220 nm (n → *) and 280 nm ( → *)
Figure S8). The spectrum of CP1 shows absorption maxima
200 nm (n → *) and ~281 nm ( → *) along with a shoulder
4
. The UV-Visible spectrum of 3b has two
Figure 5. Solid state UV-Visible spectra of (a) CP1 and (b) CP1*
(
~
peak in the range 357-366 nm (due to DMF) and peaks
corresponding to d-d transition at ~493 nm, a shoulder band at
~
The UV-Visible spectrum of CP2 showed the peaks due to 3b
(~200 nm and ~280 nm), a peak at around 320 nm for DMF and
a peak at ~637 nm (due to d-d transition), which is comparatively
more intense than that of CP1 (Figure S9). Natural distortion
along with extreme Jahn Teller distortion (d9 resulting in
542 nm and another hump ~627 nm (Figure 5).[74] If Co(II) is
assumed to be of perfect octahedral geometry in CP1 then the d-
d transition can be labelled as ~493 nm ( T1g (F) → 4
4
T1g(P)) and
~
621 nm (4T1g(F) → 4A2g(P)) in accordance with the Tanabe
g
asymmetry in e orbital) is quite evident from the crystal structure
7
Sugano diagram for d high spin system. The shoulder band ~542
nm indicates that the Co(II) has a distorted geometry resulting in
lowering of the degeneracy of the ground electronic state. Along
with natural distortion, Jahn Teller distortion is also evident from
analysis of CP2. In fact, the tetragonal elongation observed in
−
CP2 is so extreme that one of the SCN is beyond the bonding
distance. Such distortions in CP2 has a direct effect in the
intensity of the d-d transition bands which showed an increased
molar extinction coefficient. The band gap (E ) was calculated by
g
7
the fact that d high spin state will have asymmetry in the t2g orbital
and is expected to show tetragonal compression. The tetragonal
compression is also clear from the crystal structure, but the extent
of distortion is not so pronounced in terms of bond lengths. The
natural distortion in the bond angle i.e deviation from 90°, is due
to the steric factors.
Tauc plot. The band gap of CP1 was found to be 2.14 eV while
that in CP2 was calculated as 1.30 eV (Figure 6a).
Photocatalytic Degradation of Organic Dye Molecules
The band gap of CP1 (2.14 eV) and CP2 (1.30 eV) showed that
these CPs can act as potential photocatalyst. Photocatalytic
activity of CP1 and CP2 toward the degradation of organic dyes
was studied. The organic dye molecules, Methylene blue (MB),
Rhodamine B (RB), Methyl orange (MO) and Malachite green
(MG), were selected, which are considered as water pollutants.
For photocatalytic activity, 20 mg of CP (CP1 or CP2) is added to
20 mL of 10− M aqueous solution of an organic dye (MB, RB, MO
or MG) and the mixture was kept under ordinary light. The UV
Visible absorption spectrum was recorded after every 30 min. time
interval to analyze the decay of the dye. Similar dye degradation
experiment was done under UV light as well. Figure 7 represents
the percentage of dye degradation by CP1 and CP2 in mol %.
CP1 has DMF guest molecules, which were removed by heating
CP1 crystals at a temperature of 120 °C under vacuum. The
resultant crystals, CP1*, showed a significant color change, which
may be attributed to changes in the d-d transition (Figure 5). The
UV-Visible spectrum of CP1* was recorded and a substantial
decrease in the intensity of the peak in the range 357-366 nm was
observed, which confirmed the removal of DMF. Further the peak
due to d-d transition, ~493 nm (4T1g(F) → 4T1g(P)), also showed a
reduction in intensity. In fact, the two d-d transition peaks, ~493
nm (4T1g(F) → 4T1g(P)) and ~627 nm (4T1g(F) → A2g(P)), were
now observed to have almost similar intensity, with a quite less
molar extinction coefficient. It may be inferred from the UV-Visible
spectrum that on removing the DMF, distortions along the Co(II)
coordination sphere in CP1* has reduced, thereby validating the
Laporte selection rule and consequently the reduction in molar
extinction coefficient. The C=O of the DMF molecules in CP1
were involved in hydrogen bond interactions with the N-H of 3b.
5
4
It was observed that CP2 was more efficient in degrading MB, MO
and RB under ordinary light (CFL) as well as UV light than that of
CP1 (Figure S10-S25). The low band gap of CP2 compared to
that of CP1 is reflected in terms of higher photocatalytic efficiency
8
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
of CP2 than that of CP1. The kinetics of MB degradation by CP2
was found to follow 1st order kinetics and the slope plot ln [MB]
vs. time, where [MB] is the molar concentration, was used to
calculate the rate constant (3.14  10−4 s−1 for UV). Rate constant
for the photodegradation of MO, RB and MG in presence of CP2
is provided in SI (Figure S26). The mechanism of photocatalytic
degradation of organic dyes by CP1 and CP2 is depicted in Figure
6
b.[75] The lower band gap in CP2 resulted in creation of holes in
the valence band, which are involved in the reduction of water
·
·
molecules to hydroxyl radical (OH ) and the OH further carry out
the degradation of the dyes.
In order to further verify the degradation of the dyes, MB
degradation by CP2 was also analyzed by NMR spectroscopy,
where 0.01 M of MB dissolved in D
2
O solvent and its 1H-NMR
spectrum was recorded. Then the solution was kept under UV
light for one day after adding CP2. 1H-NMR spectrum of the
resultant solution showed a considerable change in the peak
position of aromatic as well as in the aliphatic region (Figure 7b).
These changes indicate phenyl rings of MB molecule has been
broken into small organic acids and inorganic ions.[76] The powder
X-ray diffraction (PXRD) pattern has shown stability of the
recovered samples after the photocatalysis (Figure S27).
Figure 7. (a) Dye degradation by CP1 and CP2 under UV and CFL light (b) (i)
1
H-NMR spectrum of MB in D
2
O and (ii) 1H-NMR spectrum of MB after
degradation by CP2 under UV light
Adsorption-Desorption of Iodine in CP1 and CP2
Polar environment created due to the presence of DMF molecules
near the loops of CP1 and CP2 has prompted us to study the
adsorption and desorption of iodine from solution. To estimate the
iodine adsorption, 5 mg of the CP (CP1 or CP2) was dipped into
a 10-4 M solution of iodine in hexane. In case of iodine adsorption
by CP1, it was observed that after 7-9 hours, pink colored crystals
of CP1 were converted to dark brown without any change in the
crystal morphology (Figure 7c). The integrity of the host
framework in the iodine adsorbed CP1 was confirmed by PXRD
studies (Figure S28-S29). The plot of ln [I
the I adsorption in CP1 and CP2 follow the first order kinetics and
the rate constants of CP1 and CP2 are calculated as 8.32  10
2
] with time showed that
2
−5
−
1
−5 −1
s
I
and 9.71  10 s , respectively (Figure S30). The amount of
adsorbed by CP1 and CP2 were found to be 95.14 mol % and
5.66 mol %, respectively (Figure 8a and Figure S31). Desorption
from I @CP1 and I @CP2 was done by soaking the
2
9
of I
2
2
2
compounds into methanol (Figure S31). The desorption process
was monitored using UV-Visible spectroscopy, wherein after 30
min. time interval, the absorbance of the solution was measured.
Figure 6. (a) Tauc plot for band gap determination in CP1 and CP2 (b)
Schematic representation of charge transfer for photocatalytic degradation in
CPs
2
For I @CP1, the absorbance at 359 nm increased with time,
which indicated the release of iodine from the CP (Figure 8b).
9
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
−1
−1
6
I
2
@CP2 has released I
2
at 265 nm within 8.5 hours and at 360 nm
ohm cm respectively at 4.48  10 Hz (Figure 9b). Initially, up
to 104 Hz, the conductivity of CP1-BT is independent of the
frequency. In the modulus vs. frequency plot, more significant shift
in peak position of CP1-BT was observed to the higher frequency
region due to the motion of the mobile charge (Figure 9c).
Dielectric permittivity increases the sharply indicating ionic
conduction mechanism is dominant at low frequency region for
CP1-BT (Figure 9d). Impedance of CP1 and CP2 are polarized at
high frequency region again proving that the accumulation of the
ionic charges at the impedance interface. CP1-BT has shown
more carrier transport to the free mobility of the ions due to the
presence of benzotriazole as guest molecules.
the negligible increase is observed.
Conclusion
1
3
N ,N -di(pyridine-4-yl)isophthalamide, an exo bidentate ligand
having amide groups in the spacer, resulted in a one dimensional
looped chain coordination polymer, CP1 and trnasmetalation
reaction on CP1 with Cu(II) formed CP2, which is also 1D looped
chain. A band gap of 2.41 eV and 1.30 eV, respectively, for
CP1and CP2 shows that these are potential photocatalysts thus
photocatalytic dye degradation studies were done which showed
a greater dye degradation efficiency of CP2 compared to that of
CP1. Presence of DMF as guest in both CP1 and CP2 has
resulted in creating polar environment thereby facilitated the
2 2
adsorption of I and the kinetics of I adsorption showed a rate
constant of 8.32  10 s−1 for CP1 and 9.71  10−5 s−1 for CP2.
Impedance measurements showed a higher conductivity in the
CP1-BT.
−5
Experimental Section
General
1H and 13C Nuclear Magnetic Resonance spectra were recorded on a 400
MHz spectrophotometer (Bruker). IR spectra were taken from Shimadzu
model-00247 IRAffinity-1S. Thermogravimetric analysis performed by
2
using Perkin Elmer TGA4000 with the flowing rate of N is 10°C/min. PXRD
were recorded with a Rigaku miniflex ll, λ =1.54 Å, Cu-K. The elemental
analysis (C, H, N, S) were performed by using Vario elemental analyzer.
UV-Visible Spectra were taken from in Jasco V-650 spectrophotometer.
Atomic absorption spectra was measured using AA-7000, Shimadzu. EDX
analysis was done by Leica Ultra Microtome EMUC7, Apreo LoVac model
with Aztec Standard EDS system-resolution 127 eV on Mn-K. The
impedance was measured by computer interfaced HIOKI impedance
analyser model IM3570. Isophthaloyl chloride and 4-aminopyridine are
purchased from Sigma Aldrich. All others chemical like DMF, KSCN,
Figure 8. (a) Adsorption of iodine by CP1, (b) Desorption of iodine from CP1,
(c) Microscope images of iodine adsorption in CP1 over time
Impedance Measurement of CP1, CP2, and Guest Absorbed
CP1
Impedance of CP1, CP2 and benzotriazole incorporated CP1,
CP1-BT (Scheme 2), were measured to study the electrical
conductivities of the CPs. Impedance, Z, is the total opposition a
device or circuit offers to the flow of an alternate current at a given
frequency. Figure 9a represents normalized impedance plot
3 2 2 3 2 2
Cu(NO ) .6H O, Co(NO ) .6H O, Methylene blue, Malachite green,
Rhodamine B, Methyl orange and solvents are purchased from reagent
grade and used further without purification.
Single Crystal X-ray Diffraction (XRD) Studies
(
Nyquist plot) of CP1, CP2 and CP1-BT. The depressed
semicircle arc in CP1-BT shows that it is a better conducting
material than CP1 and CP2. The conductivities of CP1-BT, CP1
The single crystal XRD analysis of CP1 and CP2 was done at IISER Mohali,
Punjab, using a Bruker Kappa APEX II diffractometer equipped with a CCD
detector and sealed tube monochromated Mo-K radiation. The structures
were solved by using the program APEX2. By using the program SAINT
for the integration of the data, reflection profiles were fitted, and values of
−8
-1
−1
−9
and CP2 were calculated as 5.43  10 ohm cm , 3.54  10
−1
−1
−9
−1
−1
ohm cm and 3.33  10 ohm cm respectively at the low-
frequency region and it increases with increasing frequency up to
.6  10− ohm cm , 4.43  10 ohm−1 cm , and 6.0  10
6
−1
−1
−6
−1
−6
2
2
6
F and σ(F ) for each reflection were obtained. Data were also
1
0
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Figure 9. Impedance measurement of CP1, CP2 and CP1-BT: (a) Nyquist plot, (b) Conductivities vs. frequency plot, (c) Modulus vs. frequency plot, (d) Dielectric
vs. frequency plot
corrected for Lorentz and polarization effects. The subroutine XPREP was
used for the processing of data that included determination of space group,
application of an absorption correction (SADABS), merging of data, and
generation of files necessary for solution and refinement.[77] The structure
was solved by direct methods and refined by least square methods on F2
using SHELX-97.[78] Non-hydrogen atoms were refined anisotropically and
hydrogen atoms were fixed at calculated positions and refined using a
riding model. The single crystal structural information were deposited into
the Cambridge Crystallographic Data Centre (CCDC numbers for CP1 and
CP2 are 1981911 and 1981912, respectively).
Synthesis of CP1, {[Co0.5 (3b)(NCS)]·1.5(DMF)}
n
1
0 mL ethanolic solution of Co(NO
layered slowly over a mixture of 3b (0.0318g, 0.1 mmol) and KSCN
0.0392g, 0.4 mmol) in 45 mL DMF. Pink coloured crystals were obtained
after 4-5 days. Yield: 77%. Selected FTIR peaks (KBr, cm−1): 2075 (vs),
663 (s), 1598 (s), 1512 (s), 1419 (m), 1327 (m), 1296 (m), 1242 (m), 1203
m), 1134 (m), 1010 (vs), 840 (m), 786 (m) (Figure S35). Anal. calcd for
(%): C, 54.75; H, 4.79; N, 17.66; S, 6.22; Found (%): C,
1.68; H, 4.35; N, 16.90; S, 5.46 (Figure S36). Powder XRD (Figure S37).
3 2 2
) .6H O (0.0145g, 0.05 mmol) was
(
1
(
47 7 2
C H49CoN13O S
5
1
3
Synthesis of N ,N -di(pyridine-4-yl)isophthalamide (3b)
2 2 n
Synthesis of CP2, {[Cu(3b) (NCS) ]·4(DMF)}
3b was synthesized by the usual method where isophthaloyl chloride (5
CP1 crystals were soaked into a 10 mL of DMF solution of Cu(NO
3 2 2
) .6H O
mmol) and 4-aminopyridine (10 mmol) were taken separately in 15 mL of
THF solution and kept at 0°C. Isophthaloyl chloride was added dropwise
into 4-aminopyridine which was followed by the addition of trimethylamine
(
0.0120g, 0.05 mmol). The pink color crystals were turned into blue colour
crystals within couple of hours; however the crystals of CP2 were isolated
after 2 days. Yield: 78%. Selected FTIR peaks (KBr, cm−1): 2052 (s), 1689
(
15 mmol). The white precipitate was filtered and washed with 50%
(
1
(
1
vs), 1651 (vs), 1597 (vs), 1512 (s), 1419 (s), 1388 (s), 1327 (s), 1296 (s),
203 (s), 833 (s), 717 (m) (Figure S38). Anal. calcd for C50
%):C, 54.16; H, 5.09; N, 17.69; S, 5.78; Found (%): C, 53.52; H, 3.36; N,
5.09; S, 6.15 (Figure S39). Powder XRD (Figure S37).
ethanol-water mixture. Yield 70%, melting point: 215-219˚C. Selected
FTIR peaks (KBr, cm−1): 1681(s), 1604(s), 1504(s), 1319(m), 1249(s),
1
8 2
H56CuN14O S
188(m), 1134(m), 825(s), 717(m) (Figure S32). 1H NMR (400 MHz,
DMSO-d6) δ ppm: 11.22 (s, 1H), 11.06 (s, 1H), 8.64 – 8.55 (m, 5H), 8.24
dd, J = 7.8, 1.8 Hz, 2H), 8.03 (d, J = 5.5 Hz, 2H), 7.95 (d, J = 5.6 Hz, 2H),
(
Photocatalytic Experiment
7
1
.72 (t, J = 7.8 Hz, 1H) (Figure S33). 13C NMR (101 MHz, DMSO-d
67.12, 167.03, 166.50, 160.32, 140.21, 129.56, 114.95, 109.22 (Figure
6
) δ
The photocatalytic reactions were monitored by UV-Visible
spectrophotometer. 20 mg of CP1/CP2 was taken into 10 mL of 10 M of
S34).
−5
1
1
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
a dye solution (Methylene blue (MB), Methyl orange (MO), Malachite green
CP1-BT: Selected FTIR peaks (KBr, cm−1): 2361(m), 2072(s), 1670(m),
1589(vs), 1508(vs), 1420(m), 1331(s), 1292(m), 1207(m), 1014(m),
826(m), 536(vs) (Figure S49) and PXRD (Figure S50) of CP1-BT were
recorded.
(MG) or Rhodamine B (RB)). The dye solution was kept on a magnetic
stirrer under visible light (Light source: 8W CFL light). After some specified
time intervals, 2 mL aliquots were pipetted out from the dye solution and
cleared solution was obtained by centrifugation. UV-Visible spectrometer
was used to record the absorbance of the dye solution. The following
wavelengths were monitored for each dye: MB at 664 nm, MO at 464 nm,
MG at 616 nm and RB at 554 nm. A similar experiment was repeated by
keeping the reaction mixture of CP1/CP2 and a dye solution under a light
source of 256 nm.
Acknowledgements
We gratefully acknowledge the Instrumentation facility from DST
FIST & UGC-SAP to the Department of Chemistry, BITS Pilani,
Pilani Campus. We also acknowledge the Single crystal X-ray
facility at IISER Mohali, IIT Roorkee for Magnetic measurements,
Physics department, BITS Pilani, Pilani campus for Impedance
analyzer and DST-FIST supported X-ray diffraction facility. MD
acknowledges BITS Pilani, Pilani Campus for financial assistance.
Magnetic Measurement
The magnetic measurement of CP1 was performed at IIT Roorkee using
MPMS ever cool magnetometer. 1000 oersted magnetic field was applied
by varying the temperature from 1.9K to 400K.
Thermochromism Property
Keywords: Coordination polymers
•
Transmetalation
•
Photocatalysis • Iodine Adsorption • Impedance
The thermochromism studies on CP1/CP2 were done by heating the
crystals to about 120°C, which resulted in CP1* and CP2*. Noticeable
colour change was observed after 4-5 hours. The reversibility in
thermochromism was monitored by soaking the crystals of CP1* and CP2*
back in DMF solution. Within half an hour, the colour of the crystals
changed back to their original colour.
[1]
a) J. L. C. Rowsell, O. M. Yaghi, Microporous Mesoporous Mater. 2004,
73, 3-14; b) W.-W. He, S.-L. Li, Y.-Q. Lan, Inorg. Chem. Front. 2018, 5,
279-300.
[2]
[3]
A. Dhakshinamoorthy, Z. Li, H. Garcia, Chem. Soc. Rev. 2018, 47, 8134-
8172.
CP1*: Selected FTIR peaks (KBr, cm−1): 2361(w), 2068 (vs), 1686 (w),
M. Kurmoo, Chem. Soc. Rev. 2009, 38, 1353-1379.
[
4]
W. P. Lustig, S. Mukherjee, N. D. Rudd, A. V. Desai, J. Li, S. K. Ghosh,
Chem. Soc. Rev. 2017, 46, 3242-3285.
1
5
655 (m), 1508(s), 1420(m), 1234(w), 1207(s), 1096 (m), 1072(m), 829(m),
36(s) (Figure S40). PXRD (Figure S41) and TGA (Figure S42) was
[
5]
S. K. Bhardwaj, N. Bhardwaj, R. Kaur, J. Mehta, A. L. Sharma, K.-H. Kim,
A. Deep, J. Mater. Chem. 2018, 6, 14992-15009.
recorded.
[
[
6]
7]
J. Della Rocca, D. Liu, W. Lin, Acc. Chem. Res. 2011, 44, 957-968.
A. Nangia, G. R. Desiraju, Supramolecular synthons and pattern
recognition, Vol. 198 (Eds.: E. Weber), Springer, 1998, pp. 57-95.
N. Stock, S. Biswas, Chem. Rev. 2011, 112, 933-969.
CP2*: Selected FTIR peaks (KBr, cm−1): 2052 (s), 1690 (m), 1651(s),
1593(s), 1512(vs), 1423(m), 1389(m),1327(m), 1296(m), 1207(s), 1099(m),
29(m), 540(vs) (Figure S43). PXRD (Previous Figure S41) and TGA
8
[
8]
(
Figure S44) was recorded.
[9]
a) J. C. MacDonald, G. M. Whitesides, Chem. Rev. 1994, 94, 2383-2420;
b) M.-L. Tong, Y.-M. Wu, J. Ru, X.-M. Chen, H.-C. Chang, S. Kitagawa,
Inorg. Chem. 2002, 41, 4846-4848.
Iodine Adsorption and Desorption Studies
[
10] J. L. Sessler, P. A. Gale, W.-S. Cho, in Anion Receptor Chemistry, Vol. 8
(Eds.: J. F. Stoddart), Royal Society of Chemistry, 2006, pp. 370-401.
11] N. Adarsh, D. K. Kumar, P. Dastidar, CrystEngComm 2009, 11, 796-802.
12] N. Adarsh, D. K. Kumar, P. Dastidar, Inorg. Chem. Commun. 2008, 11,
0 mg of CP1/CP2 were immersed into 3 mL of 10−4 M iodine solution in
hexane. After 30 minutes time intervals, the absorbance of the solution
was measured (Absorbance maxima for I is at 522 nm). This process was
continued until the absorbance was diminished. After that colorless
hexane solution was decanted off and the iodine adsorbed crystals
1
[
[
2
6
36-642.
[
13] a) N. Adarsh, P. Dastidar, Cryst. Growth Des. 2010, 11, 328-336; b) N.
Adarsh, P. Sahoo, P. Dastidar, Cryst. Growth Des. 2010, 10, 4976-4986.
14] N. Adarsh, P. Dastidar, Cryst. Growth Des. 2009, 10, 483-487.
15] N. Adarsh, A. Grꢀlard, E. J. Dufourc, P. Dastidar, Cryst. Growth Des.
(
I
2
@CP1 and I
2 2
@CP2) were dried. The iodine adsorbed crystals, I @CP1
[
[
and I @CP2, were soaked into a methanolic solution for the desorption
2
process. After a time, interval of 30 mins., the absorbance was recorded
at  = 359 nm.
2012, 12, 3369-3373.
[
[
16] S. Ghosh, P. S. Mukherjee, Organometallics 2008, 27, 316-319.
17] S. Ghosh, B. Gole, A. K. Bar, P. S. Mukherjee, Organometallics 2009, 28,
I
1
1
2
@CP1: Selected FTIR peaks (KBr, cm−1): 2361(m), 2068(s), 1686(w),
659(m), 1589(vs), 1504(vs), 1331(m), 1288(m), 1234(w), 1207(m),
099(w), 1014(m), 829(m), 536(vs) (Figure S45 PXRD (Figure S28) and
4
288-4296.
18] S. Shanmugaraju, S. A. Joshi, P. S. Mukherjee, Inorg. Chem. 2011, 50,
1736-11745.
19] A. K. Bar, S. Shanmugaraju, K.-W. Chi, P. S. Mukherjee, Dalton Trans.
011, 40, 2257-2267.
20] S. Shanmugaraju, H. Jadhav, Y. P. Patil, P. S. Mukherjee, Inorg. Chem.
012, 51, 13072-13074.
[
[
[
1
TGA (Figure S46) were recorded.
2
I
1
1
2
@CP2: Selected FTIR peaks (KBr, cm−1): 2361(w), 2056(m), 1690(w),
655(m), 1593(vs), 1508(vs), 1389(m), 1331(m), 1292(m), 1234(m),
207(s), 1099(m), 833(m), 540(vs) (Figure S47). PXRD (Previous Figure
2
[
[
21] D. Samanta, P. S. Mukherjee, Dalton Trans. 2013, 42, 16784-16795.
22] a) S. Shanmugaraju, A. K. Bar, H. Jadhav, D. Moon, P. S. Mukherjee,
Dalton Trans. 2013, 42, 2998-3008; b) S. Shanmugaraju, A. K. Bar, K.-
W. Chi, P. S. Mukherjee, Organometallics 2010, 29, 2971-2980.
23] Y. Gong, Y. Zhou, J. Li, R. Cao, J. Qin, J. Li, Dalton Trans. 2010, 39,
9923-9928.
S29) and TGA (Figure S48) was recorded.
Impedance Measurement
[
The impedance measurements were carried out using a pellet of the
sample between the silver electrodes at room temperature (25°C) and
under wide frequency range 4Hz-5MHz using computer-interfaced HIOKI
impedance analyser model IM3570. Impedance measurements were
carried out with CP1, CP2 and CP1-BT. CP1-BT was prepared by
immersing the CP1 crystals in benzotriazole for 2-3 days.
[24] L.-W. Han, Y. Gong, Z.-J. Lin, J. Lü, R. Cao, Dalton Trans. 2012, 41,
4146-4152.
[25] Y. Gong, Y.-C. Zhou, T.-F. Liu, J. Lü, D. M. Proserpio, R. Cao, Chem.
Commun. 2011, 47, 5982-5984.
1
2
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
[
[
[
[
[
26] Y. Gong, J. Li, J. Qin, T. Wu, R. Cao, J. Li, Cryst. Growth Des. 2011, 11,
662-1674.
27] Y. Gong, J. Li, P.-G. Jiang, Q.-F. Li, J.-H. Lin, Dalton Trans. 2013, 42,
603-1611.
28] N. L. Yue, D. J. Eisler, M. C. Jennings, R. J. Puddephatt, Inorg. Chem.
004, 43, 7671-7681.
29] Z. Qin, M. C. Jennings, R. J. Puddephatt, Chem. Commun. 2002, 354-
55.
30] a) K. Banerjee, S. Roy, M. Kotal, K. Biradha, Cryst. Growth Des. 2015,
[61] P. Mahata, G. Madras, S. Natarajan, J. Phys. Chem. B 2006, 110, 13759-
13768.
1
[62] J.-P. Dong, Z.-Z. Shi, B. Li, L.-Y. Wang, Dalton Trans. 2019, 48, 17626-
17632.
1
[63] C.-X. Liu, W.-H. Zhang, N. Wang, P. Guo, M. Muhler, Y. Wang, S. Lin, Z.
Chen, G. Yang, Chem. - Eur. J. 2018, 24, 16804-16813.
[64] J. Bedia, V. Muelas-Ramos, M. Peñas-Garzón, A. Gómez-Avilés, J. J.
Rodríguez, C. Belver, Catalysts 2019, 9, 52, DOI: 10.3390/catal9010052.
[65] C. M. Navarathna, N. B. Dewage, A. G. Karunanayake, E. L. Farmer, F.
Perez, E. B. Hassan, T. E. Mlsna, C. U. Pittman, J. Inorg. Organomet.
Polym. Mater. 2020, 30, 214-229.
2
3
15, 5604-5613; b) L. Rajput, S. Singha, K. Biradha, Cryst. Growth Des.
2007, 7, 2788-2795.
[
[
[
[
[
31] L. Rajput, K. Biradha, New J. Chem. 2010, 34, 2415-2428.
32] L. Rajput, K. Biradha, CrystEngComm 2009, 11, 1220-1222.
33] L. Rajput, M. Sarkar, K. Biradha, J. Chem. Sci. 2010, 122, 707-720.
34] L. L. Gong, X. F. Feng, F. Luo, Inorg. Chem. 2015, 54, 11587-11589.
35] L.-L. Dang, X.-J. Zhang, L. Zhang, J.-Q. Li, F. Luo, X.-F. Feng, J. Coord.
Chem. 2016, 69, 1179-1187.
[66] Q. Wang, Q. Gao, A. M. Al-Enizi, A. Nafady, S. Ma, Inorg. Chem. Front.
2020, 7, 300-339.
[67] G. Givaja, P. Amo-Ochoa, C. J. Gómez-García, F. Zamora, Chem. Soc.
Rev. 2012, 41, 115-147.
[68] S. Bureekaew, S. Horike, M. Higuchi, M. Mizuno, T. Kawamura, D.
Tanaka, N. Yanai, S. Kitagawa, in Materials For Sustainable Energy: A
Collection of Peer-Reviewed Research and Review Articles from Nature
Publishing Group, World Scientific, 2011, pp. 232-237.
[69] Y. Fuma, M. Ebihara, S. Kutsumizu, T. Kawamura, J. Am. Chem. Soc.
2004, 126, 12238-12239.
[
[
36] F. Luo, G.-M. Sun, A.-M. Zheng, S.-X. Lian, Y.-l. Liu, X. F. Feng, Y.-Y.
Chu, Dalton Trans. 2012, 41, 13280-13283.
37] G.-M. Sun, H.-X. Huang, X.-Z. Tian, Y.-M. Song, Y. Zhu, Z.-J. Yuan, W.-
Y. Xu, M.-B. Luo, S.-J. Liu, X.-F. Feng, CrystEngComm 2012, 14, 6182-
6
189.
[70] Y.-W. You, C. Xue, Z.-F. Tian, S.-X. Liu, X.-M. Ren, Dalton Trans. 2016,
45, 7893-7899.
[
[
38] Z.-Z. Yuan, F. Luo, Y.-M. Song, G.-M. Sun, X.-Z. Tian, H.-X. Huang, Y.
Zhu, X.-F. Feng, M.-B. Luo, S.-J. Liu, Dalton Trans. 2012, 41, 12670-
[71] S. Takaishi, M. Hosoda, T. Kajiwara, H. Miyasaka, M. Yamashita, Y.
Nakanishi, Y. Kitagawa, K. Yamaguchi, A. Kobayashi, H. Kitagawa, Inorg.
Chem. 2008, 48, 9048-9050.
12673.
39] a) M. Lalonde, W. Bury, O. Karagiaridi, Z. Brown, J. T. Hupp, O. K. Farha,
J. Mater. Chem. 2013, 1, 5453-5468; b) J. D. Evans, C. J. Sumby, C. J.
Doonan, Chem. Soc. Rev. 2014, 43, 5933-5951.
[72] K. Himoto, S. Suzuki, T. Okubo, M. Maekawa, T. Kuroda-Sowa, New J.
Chem. 2018, 42, 3995-3998.
[
[
40] S. Das, H. Kim, K. Kim, J. Am. Chem. Soc. 2009, 131, 3814-3815.
41] Y. Kim, S. Das, S. Bhattacharya, S. Hong, M. G. Kim, M. Yoon, S.
Natarajan, K. Kim, Chem. - Eur. J. 2012, 18, 16642-16648.
[73] C. Dey, T. Kundu, R. Banerjee, Chem. Commun. 2012, 48, 266-268.
[74] A. B. P. Lever, Inorganic Electronic Spectroscopy, Elsevier Pub. Co.,
Amsterdam; New York, 1968.
[
[
[
[
[
[
[
42] J. Tian, L. V. Saraf, B. Schwenzer, S. M. Taylor, E. K. Brechin, J. Liu, S.
J. Dalgarno, P. K. Thallapally, J. Am. Chem. Soc. 2012, 134, 9581-9584.
43] T. K. Pal, D. De, S. Neogi, P. Pachfule, S. Senthilkumar, Q. Xu, P. K.
Bharadwaj, Chem. - Eur. J. 2015, 21, 19064-19070.
[75] a) L. Wen, L. Zhou, B. Zhang, X. Meng, H. Qu, D. Li, J. Mater. Chem.
2012, 22, 22603-22609; b) M. Roy, A. Adhikary, A. K. Mondal, R. Mondal,
ACS Omega 2018, 3, 15315-15324; c) C.-C. Wang, J.-R. Li, X.-L. Lv, Y.-
Q. Zhang, G. Guo, Energy Environ. Sci. 2014, 7, 2831-2867.
[76] A. M. Ibrahim, S. M. Al-Ashqar, Spectrochim. Acta A 2012, 92, 238-244.
[77] A. Bruker, Bruker AXS Inc., Madison, Wisconsin, USA 2008.
[78] G. M. Sheldrick, Acta Crystallogr. Sect. A: Found. Crystallogr. 2008, 64,
112-122.
44] T.-F. Liu, L. Zou, D. Feng, Y.-P. Chen, S. Fordham, X. Wang, Y. Liu, H.-
C. Zhou, J. Am. Chem. Soc. 2014, 136, 7813-7816.
45] M. Gupta, D. De, S. Pal, T. K. Pal, K. Tomar, Dalton Trans. 2017, 46,
7
619-7627.
46] S. Bommakanti, U. Venkataramudu, S. K. Das, Cryst. Growth Des. 2018,
9, 1155-1166.
47] K. Suman, F. Baig, V. K. Gupta, S. Mandal, M. Sarkar, RSC Adv. 2014,
, 36451-36457.
1
4
48] S. Khan, A. Malik, in Environmental Deterioration and Human Health:
Natural and Anthropogenic Determinants (Eds.: A. Malik, E. Grohmann,
R. Akhtar), Springer Netherlands, Dordrecht, 2014, pp. 55-71.
[
[
[
49] a) F. Zhang, Y.-H. Li, J.-Y. Li, Z.-R. Tang, Y.-J. Xu, Environ. Pollut. 2019,
253, 365-376; b) N. Zhang, M.-Q. Yang, S. Liu, Y. Sun, Y.-J. Xu, Chem.
Rev. 2015, 115, 10307-10377.
50] a) S. Martha, P. Chandra Sahoo, K. M. Parida, RSC Adv. 2015, 5, 61535-
61553; b) M. M. Khan, S. F. Adil, A. Al-Mayouf, J. Saudi Chem. Soc. 2015,
19, 462-464.
51] S. Gautam, H. Agrawal, M. Thakur, A. Akbari, H. Sharda, R. Kaur, M.
Amini, J. Environ. Chem. Eng. 2020, 8, 103726.
[
[
52] L. L. Zhang, Z. Xiong, X. S. Zhao, ACS Nano 2010, 4, 7030-7036.
53] L. Gu, J. Wang, H. Cheng, Y. Zhao, L. Liu, X. Han, ACS Appl. Mater.
Interfaces 2013, 5, 3085-3093.
[
[
[
54] L. Yuan, M.-Q. Yang, Y.-J. Xu, Nanoscale 2014, 6, 6335-6345.
55] Z.-R. Tang, Y. Zhang, N. Zhang, Y.-J. Xu, Nanoscale 2015, 7, 7030-7034.
56] B. Weng, M.-Y. Qi, C. Han, Z.-R. Tang, Y.-J. Xu, ACS Catal. 2019, 9,
4642-4687.
[
[
[
[
57] S. Dhaka, R. Kumar, A. Deep, M. B. Kurade, S.-W. Ji, B.-H. Jeon, Coord.
Chem. Rev. 2019, 380, 330-352.
58] Z. Wu, X. Yuan, J. Zhang, H. Wang, L. Jiang, G. Zeng, ChemCatChem
2
017, 9, 41-64.
59] L. Liu, J. Ding, C. Huang, M. Li, H. Hou, Y. Fan, Cryst. Growth Des. 2014,
4, 3035-3043.
1
60] S. Bala, S. Bhattacharya, A. Goswami, A. Adhikary, S. Konar, R. Mondal,
Cryst. Growth Des. 2014, 14, 6391-6398.
1
3
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000450
FULL PAPER
Entry for the Table of Contents
Key Topic – Single crystal to single crystal transmetalation; Dye degradation
1
3
Transmetalation reaction with Cu(II) on a one-dimensional looped chain coordination polymer (CP1) of Co(II) with N ,N -di(pyridine-4-
yl)isophthalamide resulted in CP2. CP1 and CP2 were found to have band gap of 2.41 eV and 1.30 eV, respectively, and photocatalytic
dye degradation studies showed that CP2 showed much greater efficiency in degrading the dyes (Methylene blue, Methyl orange and
Rhodamine B) as compared to that of CP1. Polar nature of the loops of the chains in CP1 and CP2 due to the presence of DMF was
2
exploited to study the adsorption and desorption of I . Impedance measurements showed a higher conductivity in the benzotriazole
incorporated CP1.
1
4
This article is protected by copyright. All rights reserved.