Nona- and undecanuclear nickel phosphonate cages

Article abstract of DOI:10.1016/j.ica.2015.10.003

The bulky phosphonate ligands CarbmPO₃H₂ (((9H-carbazol-9-yl)methyl)phosphonic acid) and CarbePO₃H₂ ((2-(9H-carbazol-9-yl)ethyl)phosphonic acid) were employed to construct cages [Ni₉{(py)₂CO₂}₂(CarbmPO₃)₄(^tBuCO₂)₆(tBuCO₂H)₂(CH₃CN)₂] 1 and [Ni₁₁{(py)₂CO₂}₂(CarbePO₃)₄(^tBuCO₂)₁₀(CH₃CN)₂] 2 with (py)₂CO (di-2-pyridyl ketone) and Hpiv (pivalic acid) as coligands under solvothermal conditions. The metallic cores of cages 1 and 2 display vertex-sharing tetragonal pyramidal and tetra-capped octahedral arrangements, respectively. Magnetic property measurements indicate the coexistence of antiferromagnetic and ferromagnetic interactions between nickel centers for both cages.

Full text of DOI:10.1016/j.ica.2015.10.003

Inorganica Chimica Acta 439 (2016) 77–81
Contents lists available at ScienceDirect
Inorganica Chimica Acta
journal homepage: www.elsevier.com/locate/ica
Nona- and undecanuclear nickel phosphonate cages
a
Xiaoyan Tang a, Qixuan Zhong a, Jingkun Hua a, You Song b, Yunsheng Ma a, , Hongjian Cheng ,
⇑
a,
Bo Wei a, , Rongxin Yuan
⇑
⇑
a Key Laboratory of Advanced Functional Materials, School of Chemistry & Materials Engineering, Changshu Institute of Technology, Changshu 215500, PR China
b State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 27 July 2015
Received in revised form 28 September 2015
Accepted 1 October 2015
Available online 23 October 2015
The bulky phosphonate ligands CarbmPO3H2 (((9H-carbazol-9-yl)methyl)phosphonic acid)
and CarbePO3H2 ((2-(9H-carbazol-9-yl)ethyl)phosphonic acid) were employed to construct cages
[Ni9{(py)2CO2}2(CarbmPO3)4(tBuCO2)6(tBuCO2H)2(CH3CN)2] 1 and [Ni11{(py)2CO2}2(CarbePO3)4(tBuCO2)10
(CH3CN)2] 2 with (py)2CO (di-2-pyridyl ketone) and Hpiv (pivalic acid) as coligands under solvothermal
conditions. The metallic cores of cages 1 and 2 display vertex-sharing tetragonal pyramidal and
tetra-capped octahedral arrangements, respectively. Magnetic property measurements indicate the
coexistence of antiferromagnetic and ferromagnetic interactions between nickel centers for both cages.
Ó 2015 Elsevier B.V. All rights reserved.
Keywords:
Nickel
Phosphonate
Cage
Magnetic property
1. Introduction
structural, and magnetic studies of nona- and undecanuclear nickel
carbazolyl-phosphonate cages that contain undecanuclear nickel
Metal phosphonate clusters or cages are attractive owing to
their aesthetical structures and potential applications in the fields
of biological chemistry [1] and molecular materials science [2]
such as single molecular magnets (SMMs) or low-temperature
magnetic refrigerants. RPO32ꢀ (R = aryl or alkyl) are good ligands
to build such materials because phosphonate can bind many metal
ions, compared to carboxylate, to afford various 3d [3], 3d–4f [4]
and 4f [5] clusters. There are fewer nickel phosphonate clusters,
with only eleven examples found in the literature, due to their
low crystallinity [6]. These clusters have Ni8, Ni9, Ni10 and Ni12
cores. The cluster nuclearity depends on the phosphonate used
(R = methyl, t-butyl, phenyl, benzyl, NapCH2, p-tert-butylphenyl
and p-tert-butylbenzyl) and the use of coligands Hchp (6-chloro-
2-hydroxypyridine) and Hmhp (6-methyl-2-hydroxypyridine).
The magneto-structural correlations were investigated, Ni–O–Ni
angles smaller than 99° tend to give ferromagnetic coupling,
whereas wider angles favour antiferromagnetic interactions [6a].
In our recent work, we have demonstrated that bulky ligands
bearing carbazolyl group could increase the ability of crystalliza-
carbazolyl-phosphonate cages that contain two co-ligands (py)2CO
and Hpiv. To the best of our knowledge, compound 2 is the first
undecanuclear nickel phosphonate cage, even though a number
of Ni11 cages have been reported so far [8].
2. Experimental
2.1. Materials and methods
CarbmPO3H2 [9] and [Ni2(H2O)(tBuCO2)4(tBuCO2H)4] [10] were
prepared according to the literature method. All other starting
materials were purchase as reagent grade and used without further
purification. Elemental analyses were performed on a Perkin Elmer
240C elemental analyzer. The IR spectra were obtained as KBr disks
on a VECTOR 22 spectrometer. The magnetic susceptibility data
were obtained on a microcrystalline sample, using a Quantum
Design MPMS-XL7 SQUID magnetometer. Diamagnetic corrections
were made for both the sample holder and the compound esti-
mated from Pascal’s constants [11].
tion of the products. This is because the large p-conjugating groups
could form strong intermolecular interactions [7]. In the pursuit of
new clusters with interesting physical properties, we extend our
research on nickel phosphonate. Herein, we report the synthesis,
2.2. Synthesis of (2-(9H-carbazol-9-yl)ethyl)phosphonic acid
To carbazole (1.86 g, 11.13 mmol) in dry DMSO (20 mL) NaH
(0.49 g, 12.24 mmol) was added, and the solution was stirred for
0.5 h at room temperature under N2. Then, diethyl (2-bro-
moethyl)phosphonate (2.64 g, 12.24 mmol) was added and the
⇑
Corresponding authors.
E-mail addresses: myschem@hotmail.com (Y. Ma), yuanrx@cslg.edu.cn
(R. Yuan).
http://dx.doi.org/10.1016/j.ica.2015.10.003
0020-1693/Ó 2015 Elsevier B.V. All rights reserved.

78
X. Tang et al. / Inorganica Chimica Acta 439 (2016) 77–81
mixture was heated at 60 °C for 20 h. The reaction mixture was
poured into water (100 mL), acidified with 1 M hydrochloric acid
and then extracted with ethyl acetate (3 ꢁ 100 mL). The combined
organic extracts were washed with brine, dried with magnesium
sulfate and the solvent was removed. The residue was dissolved
in a minimum amount of ethyl acetate and chromatographic
separation on silica was achieved by eluting with pet. ether:ethyl
acetate (2:1). The solvent was removed under reduced pressure to
give diethyl(2-(9H-carbazol-9-yl)ethyl)phosphonate as pale yellow
liquid (1.37 g, 37.02%). To diethyl(2-(9H-carbazol-9-yl)ethyl)-
phosphonate (3.32 g, 10 mmol) in dry CH2Cl2 (20 mL) trimethylsilyl
bromide (2.90 mL, 22 mmol) was added under N2. The solution
was stirred for 6 h before being quenched with MeOH and stirred
vigorously. After a further 2 h stirring the solvent was removed
under reduced pressure and water (5 mL) was added. The mixture
was then concentrated under reduced pressure. This step was
repeated four times to give (2-(9H-carbazol-9-yl)ethyl)phosphonic
acid as an off-white solid. The solid was recrystallized with water
to give the white solid (2.91 g, 90.94%). 1H NMR (DMSO, 400 MHz):
8.16 (d, 2H, J = 8.0 Hz), 7.56 (d, 2H, J = 12 Hz), 7.48 (t, 2H,
J = 8.0 Hz), 7.22 (t, 2H, J = 8.0 Hz), 4.50–4.54 (m, 2H), 2.01–2.09
(m, 2H) ppm. 13C NMR: 139.85, 126.32, 122.73, 120.88, 119.42,
109.39, 37.83, 28.40 ppm. 31PNMR: 24.05 (s). Anal. Calc. for C14H14
NO3P: C, 61.09; H, 5.13; N, 5.09. Found: C, 60.88; H, 5.00; N, 5.20%.
IR (KBr, cmꢀ1): 3415.3(s), 3048.7(w), 1618.9(vs), 1457.9(s), 1328.3
(w), 1256.6(m), 1179.6(s), 1130.2(m), 1028.1(s), 950.4(s), 745.6(s),
721.9(s), 616.9(s), 499.6(s).
the program Bruker SAINT
,
and an absorption correction
(multi-scan) was applied. The reflection data were also corrected
for Lorentz and polarization effects. The structures were solved
by direct methods and refined on F2 by full matrix least squares
using SHELXTL. All of the non-hydrogen atoms were located from
the Fourier maps, and were refined anisotropically. All H atoms
were refined isotropically, with the isotropic vibration parameters
related to the non-H atom to which they are bonded. The structure
of compounds 1 and 2 contains solvent-accessible voids; hence, the
SQUEEZE [12] module of the program suite PLATON was used to gener-
ate a fresh reflection file. The void volume and void count electrons
are 2551 and 417 for 1, 644 and 56 for 2, which indicate the pres-
ence of nine CH3CN and one CH3CN molecules in each molecules.
The crystallographic and refinement details are listed in Table 1.
Selected bond lengths and angles are given in Tables S1–S4,
respectively.
3. Results and discussion
3.1. Synthesis
Both complexes follow a general synthetic procedure of react-
ing [Ni2(H2O)(tBuCO2)4(tBuCO2H)4] with RPO3H2 (R = Carbm,
Carbe) and (py)2CO in MeCN under solvothermal condition. The
mole ratio of starting reactants has impacts on the formation of
the final products. If [Ni2(H2O)(tBuCO2)4(tBuCO2H)4] is reacted
with CarbmPO3H2 and (py)2CO in a 1:1:0.8 M ratio crystals of 1
formed. Changing the reactants’ molar ratio we obtain very fine
green crystals. While, replacing CarbmPO3H2 with CarbePO3H2 in
the 1:1:0.8 mole ratio we obtained several green crystals with pale
precipitate. X-ray determination shows that the green crystal has
the same core to 1. Pure crystals of 2 were formed when the ratio
is 1:2:0.8. When (2-(9H-carbazol-9-yl)propyl)phosphonic acid was
used in the reaction system, no good crystals formed. The coligand
(py)2CO shows the doubly deprotonated anion gem-diol form
((py)2CO22ꢀ) in both cages [13] The trying to obtain hemiketal form
[(py)2C(OR)(OH)] of (py)2CO in other solvents such as MeOH does
not succeed. Ligand (py)2CO is important for the formation of title
nickel clusters. Without (py)2CO, clusters Ni12 and Ni8 would be
obtained with similar cores to the reported ones [6]. The stability
for both compounds were checked. When exposed on the air,
compound 1 lost its crystallinity, while compound 2 could keep
the crystallinity.
2.3. Synthesis of
[Ni9{(py)2CO2}2(CarbmPO3)4(tBuCO2)6(tBuCO2H)2(CH3CN)2] 1
CarbmPO3H2 (0.0261 g, 0.1 mmol) and [Ni2(H2O)(tBuCO2)4
(tBuCO2H)4] (0.1 g, 0.1 mmol) were dissolved in MeCN (18 mL)
and stirred for 20 h. To this was added (py)2CO (0.015 g,
0.081 mmol) and keep on stirring for another 4 h. The resulting
solution was transferred into a 20 mL Teflon-lined autoclave and
heated at 120 °C for 48 h, then cooled to room temperature at a
rate of 0.1 °C minꢀ1. Green block crystals of 1 were collected. Yield:
46% (based on Ni). Anal. Calc. for C136H163N19Ni9O32P4: C, 50.60; H,
5.09; N, 8.24. Found: C, 50.32; H, 4.78; N, 8.01%. IR (KBr, cmꢀ1):
2956.2(w), 2923.4(w), 1628.80(vs), 1578.5(vs), 1481.9(s), 1460.2
(s), 1418.7(s), 1325.2(s), 1229(m), 1170.7(s), 1080.0(s), 995.8(s),
891.04(m), 749.7(s), 551.4(w).
2.4. Synthesis of [Ni11{(py)2CO2}2(CarbePO3)4(tBuCO2)10(CH3CN)2] 2
Table 1
CarbePO3H2 (0.0275 g, 0.1 mmol) and [Ni2(H2O)(tBuCO2)4
(tBuCO2H)4] (0.2 g, 0.2 mmol) were dissolved in MeCN (18 mL)
and stirred for 20 h. To this was added (py)2CO (0.015 g,
0.081 mmol) and keep on stirring for another 4 h. The resulting
solution was transferred into a 20 mL Teflon-lined autoclave and
heated at 120 °C for 48 h, then cooled to room temperature at a
rate of 0.1 °C minꢀ1. Green block crystals of 2 were collected. Yield:
55% (based on CarbePO3H2). Anal. Calc. for C134H163N11Ni11O36P4:
C, 49.17; H, 5.02; N, 4.71. Found: C, 49.01; H, 4.85, N, 4.90%. IR
(KBr, cmꢀ1): 2956.7(m), 2866.5(w), 1567.0(vs), 1507.7(vs), 1421.2
(vs), 1230.5(s), 1177.8(w), 1153.7(w), 1036.4(s), 999.6(s), 749.1(s).
Crystal data and structure refinement for 1 and 2.
1
2
Formula
Formula weight
crystal system
Space group
a (Å)
b (Å)
c (Å)
b (°)
C
136H163N19Ni9O32P4 C134H163N11Ni11O36P4
3227.99
monoclinic
P21/c
19.0523(9)
19.3651(9)
23.4670(11)
113.1180(11)
2
1.192
1.141
59611/14494
7307
3273.30
monoclinic
P21/n
19.865(4)
16.906(3)
23.589(5)
106.31(3)
2
1.412
1.444
61795/13370
9383
Z
Dcalc (g cmꢀ3
)
l
(mmꢀ1
Total/unique reflections
)
2.5. Crystallography
Observed data [I > 2.0r(I)]
Rint
0.099
1.046
0.0604, 0.1557
0.1231, 0.1739
ꢀ0.39, 0.41
0.109
1.067
0.0746, 0.1501
0.1174, 0.1689
ꢀ0.53, 0.86
Single crystals of dimensions 0.25 ꢁ 0.20 ꢁ 0.15 mm3 for 1,
0.24 ꢁ 0.18 ꢁ 0.14 mm3 for 2 were used for structural determina-
tions on a Bruker APEX-II diffractometer using graphite monochro-
matized Mo Ka radiation (k = 0.71073 Å) at room temperature. Cell
parameters were refined by using the program Bruker SAINT on all
Goodness-of-fit (GOF) F2
R1, wR2 [I > 2.0
R1, wR2 (all data)
)maximum, (
minimum (e Åꢀ3
r
(I)]a
(D
q
Dq)
)
a
R1
=
R
||Fo| ꢀ |Fc|/
R
|Fo|; wR2 = {
R
w(F2o ꢀ F2c)2/
R
w(F2o)2}1/2
.
observed reflections. The collected data were reduced by using

X. Tang et al. / Inorganica Chimica Acta 439 (2016) 77–81
79
3.2. Structural description
bonded. There are ten 2.11 pivalates, eight of them bridge the
prism to the caps, while the remaining lie at the equator position
bridging Ni1 and Ni3 atoms. Two terminal MeCN molecules bond
to the Ni6 atoms. A second perspective of the undecanuclear core
reveals a similar arrangement to compound 1 but with two Ni
atoms being bonded on each side of the Ni9 core. The Ni sites are
all six coordinated in distorted octahedral geometries, with the
average Ni–O and Ni–N bond lengths of 2.074 Å and 2.040 Å,
respectively. These distances are close to the corresponding ones
Compound 1 crystallizes in the monoclinic space group P21/c, in
the asymmetric unit there are four and a half nickel ions, two
CarbmPO23ꢀ, one (py)2CO22ꢀ, three pivalates, one pivalic acid and
one CH3CN. The metallic core displays vertex-sharing distorted
square pyramidal arrangement with the central Ni1 as the shared
apex of two square pyramids (Fig. 1 and Fig. S1). One CarbmPO32ꢀ
ligand adopts the 5.311 [Harris notation] [14] bonding mode
(Scheme 1), with O7A as the
and Ni3 atoms. While, the other CarbmPO23ꢀ ligand adopts the
4.211 bonding mode, with O16 as the 2-O to bind with Ni2A and
l
3-O to coordinate with Ni1, Ni2A
observed in [Ni2(l2-OH2)(1,3-BDC)2(tpcb)]n [15a], [Ni2(bpb)2
(oba)2(DMF)(H2O)]2ꢂ5H2O [15b], [Ni3(oba)2(bpe)2(SO4)(H2O)4]ꢂ
l
H2O [15c] and [Ni(L)(H2O)]ꢂH2O [15d].
Ni3 atoms. Thus Ni2A and Ni3 atoms are doubly bridged by O7A
and O16 atoms with the Ni2A–O7A–Ni3 and Ni2A–O16–Ni3 bond
angles of 85.37 and 98.95°, respectively. The remaining Ni4 and
Ni5 atoms are bridged by two O–P–O groups from two different
CarbmPO23ꢀ groups. The (py)2CO22ꢀ ligand adopts the 5.1331
coordination mode to bind with Ni1 to Ni5 atoms, the Ni1–O6A–Ni4,
Ni1–O6A–Ni2, Ni1–O5–Ni5 and Ni1–O5–Ni3 bond angles are
128.03, 94.25, 127.03 and 95.99°, respectively. There are six pivalate
groups binding in a 2.11 mode. The remaining two pivalic acid and
two MeCN are found to lie terminal, coordinating to Ni4 and Ni5,
respectively. The Ni1, Ni2A and Ni3 sites are all six coordinated in
distorted octahedral geometries, while, Ni4 and Ni5 sites are tetrag-
onal pyramid. The average Ni–O and Ni–N bond lengths are 2.146 Å
and 2.043 Å, respectively, fall in a range similar to the reported com-
3.3. Magnetic properties
The variable-temperature dc magnetic behavior of 1 and 2 has
been performed on polycrystalline samples in the temperature
range of 1.8–300 K, in a magnetic field of 0.1 T (Figs. 3 and 4).
The room temperature
v
MT values are 11.84 and 14.59 cm3 -
K molꢀ1 for 1 and 2, respectively. These values are consistent with
9 and 11 uncoupled NiII centers (S = 1) with g values greater than 2,
as expected for octahedral NiII ions. The
vMT products for 1
increase gradually upon lowering the temperature, before a rapid
drop below 50 K, reaching 7.25 cm3 K molꢀ1 at 1.8 K. This behavior
shows that the presence of ferromagnetic and antiferromagnetic
interactions between the metal ions. The rapid drop at low temper-
ature is due to the zero-field splitting of the ground state. The M/
Nb versus H plot for 1 at 2 K shows a steady increase with field that
pound [6]. The core structure is different from [Ni9(
(HO3PCH2C6H5)(O3PCH2C6H5)(chp)4 (tBuCO2)8(tBuCO2H)2(H2O)], in
which two {Ni4( -OH)2} butterflies of nickel ions are holding
l3-OH)3(l2-OH2)
l
reach 11
l
B at 7 T without any saturation. The lower values are
B, g = 2). The
together by two phosphonate ligands and one additional nickel cen-
tre being bound to the cage [6a].
inconsistent with 9 uncoupled Ni2+ ions (18
l
unsaturated behavior of the plots can be explained by assuming
strong magnetic anisotropy of the ions present with high nuclear-
ity, resulting in many spin states populated at low temperature
[6c].
The magnetic interaction for 1 was modelled after taking sym-
metry-related unit into consideration (Fig. 5) with the Hamiltonian
given in Eq. (1). The first exchange pathway (J1) is assigned to the
Compound 2 is an undecanuclear cage, which crystallizes in the
monoclinic space group P21/n. The asymmetric unit contains
half of the [Ni11{(py)2CO2}2(CarbePO3)4(tBuCO2)10(CH3CN)2] cage
(Fig. 2). The metallic core arrangement of 2 shows that six of the
ions (Ni1, Ni3, Ni6, Ni1A, Ni3A and Ni6A) lie on the vertices of an
octahedron, with each of the atoms (Ni4, Ni5, Ni4A and Ni5A) cap-
ping on one face (Fig. S2). The Ni2 atom locates on the center. Of
the four phosphonate ligands present, two adopt the 5.222 bond-
ing mode, with Ni6 being chelated by the O–P–O group. The others
adopt 6.321 bonding mode, with Ni1, Ni2 and Ni3 atoms being
six Niꢂ ꢂ ꢂNi vectors bridged by two
Niꢂ ꢂ ꢂNi vectors bridged by only one
phonate or
l-O atoms, J2 is assigned to eight
l
-O atom as well as -phos-
l
l
-pivalates. All Niꢂ ꢂ ꢂNi contacts not bridged by a
monoatomic bridge were neglected, and an excellent fit of the
data was achieved above 50 K with g = 2.26, J1 = 7.32 cmꢀ1, and
J2 = ꢀ2.80 cmꢀ1 (R = 2.6 ꢁ 10ꢀ6).
bonded by the
l3-O atoms [O2]. The coordination mode of
(py)2CO22ꢀ is identical to that in 1 but with Ni6 atom not being
H ¼ ꢀJ1ðSNi1SNi2 þSNi1SNi3A þSNi2SNi3A þSNi1SNi3 þSNi1SNi2A þSNi2ASNi3
ꢀJ2ðSNi1SNi4 þSNi1SNi5 þSNi2ASNi4 þSNi3SNi5 þSNi1SNi5A þSNi1SNi4A
Þ
þSNi3ASNi5A þSNi2SNi4A
Þ
ð1Þ
For 2, the magnetic behavior was modelled with the Hamilto-
nian given in Eq. (2) (Fig. 6). The first exchange pathway (J1) is
assigned to the eight Niꢂ ꢂ ꢂNi vectors bridged by two
l
-O atoms,
-O atom
as well as l-phosphonate and l-pivalates. This allows a good fit of
J2 is assigned to ten Niꢂ ꢂ ꢂNi vectors bridged by only one
l
the magnetic behavior above 50 K with g = 2.1, J1 = 5.57 cmꢀ1, and
J2 = ꢀ5.63 cmꢀ1 (R = 2.0 ꢁ 10ꢀ4). The magnetization plot shows no
sign of saturation even at higher fields as in compound 1 and can
be understood on similar grounds.
H ¼ ꢀJ1ðSNi2SNi1 þ SNi2SNi3 þ SNi1SNi3 þ SNi5SNi6 þ SNi2SNi1A þ SNi2SNi3A
þ SNi1ASNi3A þ SNi5ASNi6AÞ ꢀ J2ðSNi2SNi5 þ SNi2SNi4 þ SNi1SNi4
þ SNi2SNi5A þ SNi2SNi4A þ SNi1ASNi4A þ SNi3ASNi5A þ SNi4ASNi6A
þ SNi3SNi5 þ SNi4SNi6
Þ
ð2Þ
The magnetic exchange coupling constants can be explained on
the basis of the Ni–O–Ni bond angle. According to the reported mag-
neto-structural correlation, Ni–O–Ni angle smaller than 99° favour
Scheme 1. Coordination modes of the ligands in Harris notation.

80
X. Tang et al. / Inorganica Chimica Acta 439 (2016) 77–81
Fig. 1. (a) Ball-and stick model showing molecular structure of 1 in the crystal. Color code: green, nickel; pink, phosphorous; red, oxygen; blue, nitrogen; gray, carbon;
hydrogen atoms are omitted for clarity. (b) Frog-shaped molecular core of 1. Symmetry code: A = ꢀx, 2 ꢀ y, 1 ꢀ z. (For interpretation of the references to color in this figure
legend, the reader is referred to the web version of this article.)
Fig. 2. (a) Ball-and stick model showing molecular structure of 2 in the crystal. Color code same as in Fig. 1. (b) Cattle-shaped molecular core of 2. Symmetry code: A ꢀ x, ꢀy,
1 ꢀ z. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)
Fig. 3. Temperature dependence of
vMT vs. T. The red solid line is the best fit
Fig. 4. Temperature dependence of vMT vs. T. The red solid line is the best fit
obtained. Magnetization curves (insert graphs) measured at 2 K for compound 1.
(For interpretation of the references to colour in this figure legend, the reader is
referred to the web version of this article.)
obtained. Magnetization curves (insert graphs) measured at 2 K for compound 2.
(For interpretation of the references to colour in this figure legend, the reader is
referred to the web version of this article.)
ferromagnetic interactions, whereas wider angles tend to give anti-
ferromagnetic couplings [16]. The relevant Ni–O–Ni bond angles are
85–99°, therefore fall within the range for ferromagnetic exchange.
Here the exchange coupling constant J1 is ferromagnetic, with value
of 7.32 and 5.57 cmꢀ1 for 1 and 2, respectively. The exchange
coupling constant J2 is antiferromagnetic, with value of ꢀ2.80 and
ꢀ5.63 cmꢀ1 for 1 and 2, respectively. The relevant Ni–O–Ni angles
are 108–128°, consistent with the observed antiferromagnetic inter-
action. The lack of signals in the AC out-of-phase indicates that 1 and
2 are not SMMs (Figs. S3 and S4).

X. Tang et al. / Inorganica Chimica Acta 439 (2016) 77–81
81
of charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif. Supplementary data associ-
ated with this article can be found, in the online version, at http://
dx.doi.org/10.1016/j.ica.2015.10.003.
References
[1] (a) A. Clearfield, K.D. Demadis, Metal Phosphonate Chemistry: From Synthesis
to Applications, The Royal Society of Chemistry, London, 2011;
(b) M. Mitra, R. Ghosh, Inorg. Chem. Commun. 24 (2012) 95.
[2] Z.Y. Zheng, G.J. Zhou, Z. Zheng, R.E.P. Winpenny, Chem. Soc. Rev. 43 (2014)
1462.
[3] (a) E.I. Tolis, M. Helliwell, S. Langley, J. Raftery, R.E.P. Winpenny, Angew. Chem.,
Int. Ed. 42 (2003) 3804;
(b) S. Maheswaran, G. Vhastanet, S.J. Teat, T. Mallah, R. Sessoli, W. Wernsdorfer,
R.E.P. Winpenny, Angew. Chem., Int. Ed. 44 (2005) 5044;
(c) Y.S. Ma, Y. Song, X.Y. Tang, R.X. Yuan, Dalton Trans. 39 (2010) 6262;
(d) S. Langley, M. Helliwell, R. Sessoli, S.J. Teat, R.E.P. Winpenny, Inorg. Chem.
47 (2008) 497;
(e) V. Chandrasekhar, S. Kingsley, Angew. Chem., Int. Ed. 39 (2000) 2320;
(f) V. Chandrasekhar, L. Nagarajan, S. Hossain, K. Gopal, S. Ghosh, S. Verma,
Inorg. Chem. 51 (2012) 5605;
(g) V. Baskar, M. Shanmugam, E.C. Sanudo, M. Shanmugam, D. Collison, E.J.L.
Mclnnes, W. Wei, R.E.P. Wnpenny, Chem. Commun. (2007) 37;
(h) J.T. Li, Y.S. Ma, S.G. Li, D.K.Y.Z. Cao, Y. Li, L.M. Zheng, Dalton Trans. (2009)
5029.
Fig. 5. Models used for the data fitting of compound 1.
[4] (a) Y.Z. Zheng, M. Evangelisti, R.E.P. Winpenny, Angew. Chem., Int. Ed. 50
(2011) 3692;
(b) Y.Z. Zheng, M. Evangelisti, R.E.P. Winpenny, Chem. Sci. 2 (2011) 99;
(c) Y.Z. Zheng, M. Evangelisti, F. Tuna, R.E.P. Winpenny, J. Am. Chem. Soc. 134
(2012) 1057;
(d) Y.Z. Zheng, E.M. Pineda, M. Helliwell, R.E.P. Winpenny, Chem. Eur. J. 18
(2012) 4161;
(e) E.M. Pineda, F. Tuna, R.G. Pritchard, A.C. Regen, R.E.P. Winpenny, E.J.L.
Mclnnes, Chem. Commun. 49 (2013) 3522.
[5] (a) K.H. Zangana, E.M. Pineda, J. Schnack, R.E.P. Winpenny, Dalton Trans. 42
(2013) 14045;
(b) K.H. Zangana, E.M. Pineda, R.E.P. Winpenny, Dalton Trans. 43 (2014) 17101.
[6] (a) B.A. Breeze, M. Shanmugam, S. Tuna, R.E.P. Winpenny, Chem. Commun.
(2007) 5185;
(b) S.K. Langly, M. Helliwell, S.J. Teat, R.E.P. Winpenny, Inorg. Chem. 53 (2014)
1128;
(c) J.A. Sheikh, A. Adhikary, H.S. Jena, S. Biswas, S. Konar, Inorg. Chem. 53
(2014) 1606;
(d) N.P. Burkovskaya, M.E. Nikiforova, M.A. Kiskin, V.I. Pekhn’O, A.A. Aidorov, V.
M. Novotortsev, I.L. Eremenko, Russ. J. Coord. Chem. 38 (2012) 331.
[7] (a) Y.S. Ma, W.S. Cai, B. Chen, J.Y. Chang, X.Y. Tang, R.X. Yuan, CrystEngComm
15 (2013) 7615;
Fig. 6. Models used for the data fitting of compound 2.
(b) Y.S. Ma, X.Y. Tang, F.F. Xue, B. Chen, Y.L. Dai, R.X. Yuan, S. Roy, Eur. J. Inorg.
Chem. (2012) 1243;
4. Conclusions
(c) Y.S. Ma, Y. Yuan, H. Miao, Q.X. Zhong, X.Y. Tang, H.J. Cheng, R.X. Yuan, Inorg.
Chim. Acta 432 (2015) 64.
[8] (a) E.K. Brechin, W. Clegg, M. Murrie, S. Parsons, S.J. Teat, R.E.P. Winpenny,
J. Am. Chem. Soc. 120 (1998) 7365;
(b) C. Benelli, A.J. Blake, E.K. Brechin, S.J. Coles, A. Graham, S.G. Harris, S. Meier,
A. Parkin, S. Parsons, A.M. Seddon, R.E.P. Winpenny, Chem. Eur. J. 6 (2000) 883;
(c) R.H. Ismayilov, W.-Z. Wang, G.-H. Lee, C.-Y. Yeh, S.-A. Hua, Y. Song, M.-M.
Rohmer, M. Bénard, S.-M. Peng, Angew. Chem., Int. Ed. 50 (2011) 2045.
[9] E. Buchaca, S.P. Man, M. Motevalli, J. Wilson, A. Sullivan, New J. Chem. 34
(2010) 2592.
[10] G. Chaboussant, R. Basler, H.U. Gudel, S.T. Ochsenbein, A. Parkin, S. Parsons, G.
Rajaraman, A. Sieber, A.A. Smith, G.A. Timco, R.E.P. Winpenny, Dalton Trans.
(2004) 2758.
Research on the nickel phosphonate cages is important to
understand the magnetic properties of the molecular systems.
Two phosphonic acids bearing carbazolyl group were designed
and employed to build two odd numbered nickel cages. In addition,
the in-situ formation of deprotonated anion gem-diol form of
(py)2CO also help the crystallization of the cages. Our method
should be advantageous because we can utilize a lot of carbazole
derivatives as ligands in metal phosphonate cage system. Magnetic
studies show the coexistence of both ferromagnetic and antiferro-
magnetic interactions between the nickel centers in both cases.
Further work is in progress to synthesize novel 3d-4f clusters bear-
ing carbazolyl phosphonate ligands.
[11] O. Kahn, Molecular Magnetism, VCH Publishers Inc., New York, 1993.
[12] PLATON, A.L. Speck, J. Appl. Crystallogr. 36 (2003) 7.
[13] A. Tsohos, S. Dionyssopoulou, C.P. Raptopolou, A. Terzis, E.G. Bakalbassis, S.P.
Perlepes, Angew. Chem., Int. Ed. 38 (1999) 983.
[14] Harris notation describes the binding mode as [X.Y1Y2Y3. . .Yn], in which X is
the overall number of metals bound by the whole ligand, and each value of Y
refers the number of metal atoms attached to the different donor atoms. See:
R.A. Coxall, S.G. Harris, D.K. Henderson, S. Parsons, P.A. Tasker, R.E.P.
Winpenny, J. Chem. Soc. Dalton Trans. (2000) 2349.
[15] (a) D. Liu, J.P. Lang, B.F. Abrahams, J. Am. Chem. Soc. 133 (2011) 11042;
(b) F.L. Hu, S.L. Wang, B. Wu, H. Yu, F. Wang, J.P. Lang, CrystEngComm 16
(2014) 6354;
Acknowledgements
This work is supported by NSFC (Nos. 21001018, 21201025) and
NSF of Jiangsu Province (Nos. BK2012643, BK2012210, 12KJA150001,
14KJA150001). The six talent peaks project in Jiangsu Province.
(c) F.L. Hu, S.L. Wang, J.P. Lang, B.F. Abrahams, Sci. Rep. 4 (2014) 6815;
(d) F.L. Hu, Y. Mi, Y.Q. Gu, L.G. Zhu, S.L. Yang, H. Wei, J.P. Lang, CrystEngComm
15 (2013) 9553.
Appendix A. Supplementary material
[16] J.M. Clemente-Juan, B. Chansou, B. Donnadieu, J.-P. Tuchagues, Inorg. Chem. 39
(2000) 5515.
CCDC 1062822 and 1062823 contain the supplementary crys-
tallographic data for this paper. These data can be obtained free