Crystallographic insight-guided nanoarchitectonics and conductivity modulation of an n-type organic semiconductor through peptide conjugation

Article abstract of DOI:10.1039/c5cc01996f

Crystallographic insight-guided nanoarchitectonics of peptide-conjugated naphthalene diimide (NDI) is described. In a bio-inspired approach, non-proteinogenic α-amino isobutyric acid (Aib)- and alanine (Ala)-derived peptides orchestrated the 1D achiral and 2D chiral molecular ordering of NDI, respectively, which resulted in modulation of nanoscale morphology, chiroptical and conductivity properties.

Full text of DOI:10.1039/c5cc01996f

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ARTICLE TYPE
Crystallographic insight-guided nanoarchitectonics and conductivity
modulation of n-type organic semiconductor through peptide
conjugation†
a
b
b
a
M. Pandeeswar, Harshavardhan Khare, Suryanarayanarao Ramakumar, and T. Govindaraju*
5
Received (in XXX, XXX) Xth XXXXXXXXX 20XX, Accepted Xth XXXXXXXXX 20XX
DOI: 10.1039/b000000x
Crystallographic insight-guided nanoarchitectonics of
peptide-conjugated naphthalene diimide (NDI) is described.
In a bio-inspired approach, non-proteinogenic α-amino
isobutyric acid (Aib)- and alanine (Ala)-derived peptides
orchestrated 1D achiral and 2D chiral molecular ordering of
NDI respectively which resulted in modulation of nanoscale
morphology, chiroptical and conductivity properties.
1
0
Ingenious organisation of functional aromatic molecular systems
is one of the key challenges in the fields of chemistry, biology
1
2
2
3
3
4
4
5
0
5
0
5
0
5
1
ꢀ2
and material science. In particular, the performance of solutionꢀ
processable, flexible, organic thinꢀfilm devices is determined by
the nature of solidꢀstate molecular ordering and resultant
2
ꢀ3
nanoscale morphology on the substrate. In this context, several
strategies have been attempted to gain control over noncovalent
interactionꢀdriven
molecular selfꢀassembly of organic
3
semiconductors to achieve the desired nanoscale morphology.
However, the art of preꢀprogrammed molecular assembly and
structureꢀproperty correlation in case of selfꢀassembled molecular
materials to facilitate development of new organic electronic
devices is still in its infancy. The ideal way to investigate the
structureꢀproperty correlations of molecular materials is
essentially through the study of similar molecular structures that
2
differ in their molecular ordering. Theoretical calculations have
predicted that on account of maximum electronic coupling, faceꢀ
toꢀface πꢀπ molecular ordering facilitates a higher charge carrier
Fig. 1 (a) Molecular structures of bisꢀdipeptide conjugated NDIs 1: Aibꢀ
Aib, 2: LꢀAlaꢀLꢀAla, and 3: DꢀAlaꢀDꢀAla.The solid state structural
insights: (b) faceꢀtoꢀface (1) and edgeꢀtoꢀedge (2) stacked dimmers and
50 (c) Subsequent space fill representation of 1D (1) and 2D (2) molecular
ordering along the crystallographic a-axis and c-face respectively (solvent
molecules and hydrogen atoms have been omitted from the crystal
packing representation for clarity). (d) Schematic representation of selfꢀ
assembled 1D and 2D nanostructures of 1 and 2, respectively.
2
mobility. However such prerequisite of perfect faceꢀtoꢀface
stacked molecular organisation of organic semiconductors is
2
a
seldom met in real solidꢀstate structures.
In nature, biomolecules, specifically (poly)peptides, have
builtꢀin information to undergo highly ordered sequenceꢀspecific
molecular organisation by means of synchronised noncovalent
interactions to form complex biological materials with
1,4
55 promising nꢀtype organic semiconductor naphthalene diimide
predetermined functions. In the past few years, principles of
bioꢀinspired engineering of molecular assemblies (molecular
architectonics) has motivated the scientific community to design
the assembly of functional aromatic molecules, producing
nanomaterials with tunable molecular ordering for various
(NDI) by conjugating dipeptides. We chose to functionalise NDI
with structurally comparable unnatural and natural peptides Aibꢀ
Aib (1) and AlaꢀAla (2 and 3), respectively. They differ in just
one additional methyl group at C position in case of Aib, and are
α
4
ꢀ7
60 capable of forming unique secondary structures, as shown in Fig.
multidisciplinary applications.
1
a and 1b. The minute structural mutations (methyl groups) are
Herein, we demonstrate the bioꢀinspired structureꢀproperty
expected to influence their distinct molecular organisation.
Notably, Aibꢀrich peptides are known to promote helix
correlation via the modulation of molecular organisation of the
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our surprise, unnatural dipeptide (AibꢀAib)ꢀconjugated NDI (1)
showed 1D molecular ordering with faceꢀtoꢀface NDIꢀNDI
organisation along crystallographic aꢀaxis. The faceꢀtoꢀface 1D
orientation of NDIꢀcore is stabilized by CHꢀꢀꢀCO (αꢀmethyl on
the peptide to acyl carbon on NDI), NHꢀꢀꢀO hydrogen bond
4
5
5
6
6
7
7
8
8
9
5
0
5
0
5
0
5
0
5
0
(between peptideꢀNH and Oxygen atom from solvent molecule,
DMSO) and CHꢀꢀꢀO (between αꢀmethyl groups on peptide and
solvent molecule, DMSO) (Fig 1b&c, ESI†). In contrast, 2 and 3
displayed 2D edgeꢀtoꢀedge NDIꢀNDI molecular ordering through
β−bridgeꢀlike interactions (series of COꢀꢀꢀNH hydrogen bonds)
between the peptide backbones along the crystallographic aꢀaxis,
giving rise to a hydrogen bond network spreading across the cꢀ
face of the crystal lattice (Fig 1b&c, ESI†). Furthermore, 1
exhibited gelation propensity by forming bright cyan fluorescent
organogel in CHCl /methylcyclohexane (MCH) (90/10 v/v) with
3
minimum gelation concentration (MGC) of 1 mM (Fig 2a, inset).
On the other hand, 2 and 3 failed to form organogel under similar
conditions (Fig 2b, inset). Thus, the observed distinct solidꢀstate
molecular organisation and gelation ability of bisꢀ(AibꢀAib) (1)ꢀ
and bisꢀ(AlaꢀAla) (2 and 3)ꢀfunctionalised NDIs validated the
importance of bioꢀinspired molecular architectonics to rationally
design molecular systems with desired molecular ordering, by
utilising minute structural mutations in the form of peptide
sequence.
The consequence of distinct molecular ordering on nanoscale
morphology of 1 and 2 was examined by atomic force
microscopy (AFM) (Fig. 2aꢀb) and field emission scanning
electron microscopy (FESEM) (ESI†). The xerogel of 1 revealed
the presence of several micrometer long, highꢀaspectꢀratio 1D
tape network. AFM height profile analysis revealed 1D nanotapes
with 20ꢀ200 nm height and 50ꢀ500 nm width (Fig. 2a). On the
other hand, 2 selfꢀassembled from its solution (MCH/CHCl3:
Fig. 2 AFM micrographs (amplitude image); (a) 1D nanotape network
from xerogel of 1 and (b) 2D nanosheets form solution of 2. Insets: (a)
organogel of 1 under UV light (365 nm), a selected area AFM image of
1
D nanotapes and corresponding height profiles along the red line
(derived from height image); (b) MCH/CHCl (90/10, v/v) solution of 2
under UV light (365 nm), a selected area 3D AFM height image of single
D nanosheet and corresponding height profiles along the blue line. (c)
ATIR spectra of 1D nanotapes (i) and 2D nanosheets (ii). (d) UVꢀvis (i
and ii) and fluorescence emission (iii and iv) spectra of 1 in CHCl (gray:
i and iii) and MCH/CHCl (90/10, v/v) (red: ii and iv), respectively.
5
0
3
2
3
1
3
Arrows and blue dotted circle indicating the spectral changes and the
appearance of new absorption band, respectively.
conformation while the Alaꢀrich peptides assist β−sheet
8
formation, as in the case of spider silk proteins. The influence of
15
20
25
30
35
40
structural mutations in (bisꢀdipeptide)ꢀNDI conjugates (NDIs 1ꢀ3)
on their solidꢀstate ordering and resultant properties viz., (chiroꢀ
)optoelectronic, selfꢀassembled nanoscale morphology and
9
0/10, v/v) into thin, large surface area 2D sheets with ~ 8ꢀ20 nm
electrical conductivity was studied (Fig. 1).
thickness and 100ꢀ800 nm lateral dimensions (Fig. 2b). Thus, 1D
and 2D molecular packing observed in the single crystals were
found to be replicated in the selfꢀassembled nanoscale structures
of 1 and 2 (Fig 1c). Attenuated total reflection infrared (ATIR)
spectroscopy further provided the secondary structures of
peptides and hydrogen bonding interactions among the molecules
within the 1D nanotapes (1) and 2D nanosheets (2) (Fig 2c). 1D
nanobelts of 1 exhibited intense amideꢀI (νC=O) absorption band at
To the best of our knowledge we present crystallographic
insightꢀguided distinct solidꢀstate molecular ordering to modulate
the conducting property of nꢀtype organic semiconductor
molecule NDI by peptide conjugation, for the first time. The
impact of minute structural mutations in the form of peptides
revealed the distinct but wellꢀdefined nanostructures (1D
nanotapes and 2D nanosheets) with perfect faceꢀtoꢀface (achiral)
and edgeꢀtoꢀedge (chiral) NDIꢀNDI selfꢀassembly, respectively
ꢀ
1
1675 cm , indicating the random structure of AibꢀAib peptide
(
Fig 1bꢀd). The significance of such bioꢀinspired molecular
backbone. On the other hand, AlaꢀAla (2 and 3) displayed a
1,4ꢀ7,10a
ꢀ
1
ꢀ1
architectonics
of NDI and resultant structureꢀproperty
strong amideꢀI band at 1636 cm and a weak signal at 1682 cm ,
correlation was thoroughly studied by various spectroscopic and
microscopy techniques.
suggesting the presence of antiparallel βꢀsheet like structure
9
within the 2D nanosheets. In agreement with the solidꢀstate
In line with the strategy, we sought to investigate the molecular
ordering of bisꢀdipeptideꢀconjugated NDIs 1ꢀ3 by single crystal
Xꢀray diffraction (XRD) studies (Fig. 1b&c). The crystals of 1ꢀ3,
suitable for single crystal XRD, were grown in dimethylsulfoxide
(DMSO) by the slow solvent evaporation method. NDI 1 was
crystal structures, 2D nanosheets (2) revealed the existence of
strong intermolecular hydrogen bonding network via amide NꢀH
and C=O by displaying blueꢀshifted broad amide NꢀH symmetric
ꢀ
1
stretching band (3261 cm ) as compared to that of 1D nanobelts
ꢀ
1
of 1 (3425 cm ).
found to crystallise in the monoclinic system with P2 /n space
1
95
UVꢀvis absorption spectrum of 1 in CHCl3 exhibited
group while NDIs 2 and 3 crystallised in orthorhombic systems
vibronically wellꢀresolved absorption bands in the 300ꢀ400 nm
region, which is a characteristic of π−π∗ transitions along the
longꢀaxis of NDI chromophore (Fig. 2d). A mirror image
emission spectrum around 413 nm (λmax) suggested typical
with space group P2 2 2 . Single crystal structures revealed that
1
1 1
the imide substituents (dipeptides, 1: AibꢀAib, 2: LꢀAlaꢀLꢀAla,
and 3: DꢀAlaꢀDꢀAla) in NDIs (1-3) adopt transꢀconformation
(i.e., peptide chains on either side of NDI oriented in opposite
1
00 monomeric state in CHCl . Interestingly, absorption spectrum of
3
directions with respect to the central aromatic core) and exhibit
distinct sequenceꢀspecific molecular packing (Fig 1b) (ESI†). To
1
in MCH/CHCl3 (90/10, v/v) displayed significant
2
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hypochromicity (~ 42%), blueꢀshift (~ 5 nm) and band
broadening. Furthermore, a new band appeared in the longer
wavelength region (415 nm). The fluorescence emission spectrum
of 1 in MCH/CHCl exhibited a significantly enhanced, broad and
3
5
large Stokeꢀshifted (~ 93 nm) emission band, centred around 468
nm, with biꢀexponential lifetime values of 9 ns (18%) and 1 ns
(82%) (Fig. 2d, ESI†). This study suggests the formation of faceꢀ
toꢀface (Hꢀtype) excitonꢀcoupled NDIꢀNDI π−π stacked selfꢀ
1
0
assembly among the molecules of 1 (Fig.1b). In contrast, 2
showed redꢀshifted (~ 5 nm) absorption bands by changing the
solvent system from CHCl3 to MCH/CHCl3 (90/10, v/v).
Corresponding emission spectra displayed a large Stokeꢀshifted
broad emission band centred at 522 nm with relatively shorter
lifetime values of 4.9 ns (48%) and 1.3 ns (52%), thus, signifying
the formation of edgeꢀtoꢀedge (Jꢀtype) stacked NDIꢀNDI self
1
1
2
2
3
3
4
4
5
5
0
5
0
5
0
5
0
5
0
5
10
1
assembly. These results were further strengthened by H NMR
data (ESI†). Due to enhanced ring current shielding in faceꢀtoꢀ
face πꢀstacked arrangement, a significant upꢀfield shift (ꢀδNDI
60 ppb) was observed for NDIꢀcore protons of 1 compared to
edgeꢀtoꢀedge interacting NDIꢀcore in 2. Variableꢀtemperature
VT) emission studies of 1 and 2 monitored at 460 nm and 522
=
1
1
Fig. 3 (a) H NMR data of 1 depicting the change in the chemical shift
6
6
0
5
(ppm) values of NDI aromatic protons (blue line) and peptideꢀamide NH
(
protons (red line) as a function of volume of MCH added into CDCl
solution. (b) CD spectra of 1 (i), 2 (ii) and 3 (iii) recorded in
MCH/CHCl (90/10, v/v) solution. (c) Solidꢀstate 1D faceꢀtoꢀface achiral
3
nm, respectively, exhibited two times higher melting
temperatures (50% aggregates were intact even at 75 °C) for faceꢀ
toꢀface assembly of 1 as compared to that of edgeꢀtoꢀedge
assembly of 2 (50% aggregates were present at 38 °C) (ESI†).
The influence of MCH on the NDIꢀNDI aromatic stacking and
hydrogen bonding interactions of 1 and 2 were probed by solventꢀ
3
organisation of 1 (i), supramolecular tilt leftꢀhanded (ii, in 2) and rightꢀ
handed (iii, in 3) chiral NDI stacks from single crystal XRD studies.
and right (P)ꢀhanded supramolecular helical organisation of NDI
5c,10a
chromophores.
NDI 1 with achiral and nonꢀproteinogenic
1
dependent H NMR measurements. Fig. 3a clearly shows the upꢀ
peptide (AibꢀAib) did not show CD signal under similar
conditions, indicating the absence of any preferred helical
assembly. To validate the CD data, we further analysed solidꢀ
state molecular organisation in the single crystal packing of 1ꢀ3
(Fig. 3c). The linear 1D faceꢀtoꢀface molecular stacks of 1 in the
crystal lattice were found to coꢀexist as both leftꢀ and rightꢀ
field and downꢀfield shifting of NDIꢀaromatic (7 ppb) (faceꢀtoꢀ
face NDI selfꢀassembly) and peptideꢀamide protons (20 ppb)
7
7
8
8
9
0
5
0
5
0
(solvent induced hydrogen bonding), with the increasing volume
fraction of MCH in CDCl solution of 1 (ESI†). Under similar
3
conditions, 2 exhibited relatively less downꢀfield shift (6 ppb)
(β−bridge interactions) of peptideꢀamide protons and increased
handed 2 chiral helices, thus nullifying the chiral signature in the
1
upꢀfield shifts (8 ppb) of NDIꢀaromatic protons (edgeꢀtoꢀedge
NDI selfꢀassembly). These changes in chemical shifts suggested
that the MCH facilitated distinct selfꢀassembly among the
molecules of 1 and 2 by reinforcing the noncovalent interactions
via intermolecular NDIꢀNDI aromatic and hydrogen bonding
among the peptide chains. Furthermore, although solvent systems
used for crystal growth and nanostructures of 1 and 2 are
different, the detailed spectroscopic and microscopy studies in
CD spectra. On the other hand, 2 and 3 showed prominent 21
supramolecular tilt stacks with opposite helical assembly along
the crystallographic a and bꢀaxis. In the case of 2, the tilt angles
were found to be 30.67˚ and 59.79˚ along a and bꢀaxis,
respectively. Similarly, in the case of 3, the tilt angles were found
5c,10a
to be 30.56˚ and 59.93˚ along a and bꢀaxis, respectively.
The
pitch of the helices was found to be 9.94 Å (along a-axis) and
4.41 Å (along bꢀaxis) for 2, while for 3 the pitch was 9.99 Å
1
MCH/CHCl (90/10, v/v) support faceꢀtoꢀface (Hꢀtype) and edgeꢀ
3
(along aꢀaxis) and 14.47 Å (along bꢀaxis) (ESI†). The helices
were found to be stabilised by β−bridge like intermolecular COꢀꢀꢀ
NH hydrogen bonding between the peptide backbones. Overall,
achiral (1) and chiral (2 and 3) organisation of bisꢀdipeptideꢀ
conjugated NDIs, within the lattices of their respective crystals
toꢀedge (Jꢀtype) molecular arrangements for 1 and 2 respectively
(Fig 2. and Fig. S6d in ESI†), which is in good agreement with
XRD data.
The effect of chiral information of peptide backbones in 2 and 3
against achiral backbone in 1 on the longꢀrange intermolecular
organisation of NDI was investigated by circular dichroism (CD)
spectroscopic studies (Fig. 3b). In agreement with the UVꢀvis and
fluorescence emission data, NDIs 1ꢀ3 displayed flat CD spectra in
(Fig. 3c), is in excellent agreement with the CD data (Fig. 3b).
These results further corroborated the transcription of chiral
information of intrinsically chiral amino acid (alanine) of the
peptide backbones in 2 and 3 to their supramolecular homochiral
CHCl solution due to their molecularly dissolved state (ESI†)
3c,5c,10a
3
organisation in solution and solid state.
which also confirmed the absence of any Cotton effects
Furthermore, we examined the effect of minute structural
mutations (dipeptide) guided distinct NDI molecular organization
originating from achiral conformations of methyl (C ) group.
α
However, 2 and 3 in CHCl /MCH (90/10, v/v) displayed mirror
3
95 of 1 (1D faceꢀface) and 2 (2D edgeꢀedge) on the charge carrier
mobility (Fig 4). Twoꢀprobe method was employed to generate
the currentꢀvoltage (IꢀV) response from the films of 1 (1D
nanotapes) and 2 (2D sheets) as shown in Fig. 4a. Remarkably,
image cotton effects in the NDI absorption region (250ꢀ400 nm).
The negative and positive cotton effects of 2 and 3, around 400
nm (NDI long axis π−π∗ electronic transitions), suggests left (M)ꢀ
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b
50
Department of Physics, Indian Institute of Science, Bengaluru-560012,
India.
†
Electronic Supplementary Information (ESI) available: [Synthetic
procedure, characterization and Crystallographic information ]. See
DOI: 10.1039/b000000x/
55
‡ Crystal structure information
1
: CCDC 1015722; 2: CCDC 1015724; 3: CCDC 1015723. The
supplementary crystallographic data can be obtained from the Cambridge
Crystallographic Data Centre (CCDC) via
www.ccdc.cam.ac.uk/data_request/cif.
Fig. 4 (a) Schematic representation of currentꢀvoltage (IꢀV) device 60 1 a) L. M. Salonen, M. Ellermann and F. Diederich, Angew. Chem. Int.
fabricated using nanotapes network film from xerogel of 1 or 2D
nanosheets film from nanostructured materials of NDI. (b) IꢀV
characteristics of 1 (1D nanotapes network) (i) and 2 (2D nanosheets) (ii)
Ed., 2011, 50, 4808ꢀ4842; b) K. E. Riley and P. Hobza, Acc. Chem.
Res., 2013, 46, 927ꢀ936; c) M. B. Avinash and T. Govindaraju,
Nanoscale, 2014, 6, 13348ꢀ13369; d) K. Ariga, K. Kawakami, M.
Ebara, Y. Kotsuchibashi, Q. Ji and J. P. Hill, New J. Chem., 2014, 38,
5149ꢀ5163; e) K. Ariga, Q. Ji, W. Nakanishi, J. P. Hill and M. Aono,
Mater. Horiz., 2015, DOI: 10.1039/C1035MH00012B.
a) V. Coropceanu, J. Cornil, D. A. da Silva Filho, Y. Olivier, R. Silbey
and J.ꢀL. Brédas, Chem. Rev., 2007, 107, 926ꢀ952; b) M.; Masꢀ
Torrent and C. Rovira, Chem. Rev., 2011, 111, 4833ꢀ4856.
2
5
deposited across the aluminium electrodes as shown in (a).
6
7
7
8
8
9
5
0
5
0
5
0
the currentꢀvoltage (IꢀV) measurements on NDI 1 (1D nanotapes)
2
3
with faceꢀtoꢀface NDI organisation showed twoꢀtimes more
ꢀ
6
conductivity (3.5 ×10 S/m) as compared to NDI 2 (2D
ꢀ
6
nanosheets) with edgeꢀtoꢀedge NDI organisation (1.6 ×10 S/m).
Similar IꢀV characteristics was observed for film of 3 (2D
nanosheets) which confirmed that chirality has no role in the
modulation of conductivity in our peptide conjugated NDIs. The
significantly enhanced conductivity of 1 is attributed to perfect
faceꢀtoꢀface molecular arrangement, which is known to maximise
the electronic coupling among the π−π overlapped NDI
a) K. Sakakibara, J. P. Hill and K. Ariga, Small, 2011, 7, 1288ꢀ1308;
b) T. Aida, E. W. Meijer and S. I. Stupp, Science, 2012, 335,
813−817; c) M. Pandeeswar and T. Govindaraju, RSC Adv. 2013, 3,
1
1
2
2
3
3
4
4
0
5
0
5
0
5
0
5
1
1459ꢀ11462; d) Y. Diao, L. Shaw, Z. Bao and S. C. B. Mannsfeld,
Energy Environ. Sci., 2014, 7, 2145ꢀ2159. e) K. Ariga, Y. Yamauchi,
G. Rydzek, Q. Ji, Y. Yonamine, K. C. W. Wu and J. P. Hill, Chem.
Lett., 2014, 43, 36ꢀ68; f) X. Cheng, S. B. Lowe, P. J. Reece and J. J.
Gooding, Chem. Soc. Rev., 2014, 43, 2680ꢀ2700.
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Jatsch, E. K. Schillinger, S. Schmid and P. Bauerle, J. Mater. Chem.,
2
molecules. Therefore, difference in the conductivity values of
4
NDI chromophore in 1D nanotapes of 1 and 2D nanosheets of 2
further exemplifies the potential of bioꢀinspired molecular
architectonics guided by the crystallographic insights for the
modulation of functional properties (viz., nanoscale morphology,
2
010, 20, 3563ꢀ3578; d) M. B. Avinash and T. Govindaraju, Adv.
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In conclusion, we demonstrated the crystallographic insightꢀ
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5
guided structureꢀproperty correlation in the form of
nanomorphology, optoelectronic and conductivity behaviour of
bisꢀdipeptideꢀconjugated naphthalene diimides (NDI). In our bioꢀ
inspired design strategy, minute structural mutations played a
significant role in the modulation of functional properties of nꢀ
type organic semiconductor (NDI). The nonꢀproteinogenic
(achiral) dipeptide (AibꢀAib) promoted 1D faceꢀtoꢀface
arrangement (Hꢀtype) while the proteinogenic (chiral) dipeptide
1
6947;c) M. Pandeeswar, M. B. Avinash and T. Govindaraju, Chem.
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Bouillière, D. Wang, K. Koynov, W. Pisula, K. Müllen and H.
Wennemers, Angew. Chem. Int. Ed., 2014, 53, 12537ꢀ12541.
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5
nanostructures (1D and 2D) showed unusually high correlations,
which reflected in their distinct optoelectronic and conductivity
properties. Thus, our report on crystallographic insightꢀguided
and bioꢀinspired molecular architectonics is not only envision
novel way of engineering molecular assemblies and to undertake
structureꢀproperty correlations but it may also facilitate the
interfacing of the electronic materials with biology to enable
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The authors thank Prof. C. N. R. Rao for constant support,
JNCASR, DBT, Govt. of India (IYBA grant BT/03/IYBA/2010)
for financial support and ICMR for a research fellowship to H.K.
Notes and references
a
Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal
Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bengaluru
5
60064, India. Fax: (+) 91 80 22082627; E-mail: tgraju@jncasr.ac.in
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This journal is © The Royal Society of Chemistry [year]

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ChemComm
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DOI: 10.1039/C5CC01996F
TOC
Crystallographic insightꢀguided and bioꢀinspired molecular
nanoarchitectonics of nꢀtype organic semiconductor is described
to understand the structureꢀproperty correlation, for modulation
of functional properties. The minute structural mutations in the
form of bisꢀdipeptides orchestrated tunable molecular ordering,
nanoscale morphology, chiroptical and conductivity properties.
5
This journal is © The Royal Society of Chemistry [year]
Journal Name, [year], [vol], 00–00 | 5