Intermolecular Charge Transfer Research Articles

Quasi-intrinsic fluorescent probes for detecting the DNA adduct (ABPdG) based on an excited-state intermolecular charge transfer mechanism.

N'-(2'-Deoxyguanosin-8-yl)-4-aminobiphenyl (ABPdG) is one of the most representative carcinogenic DNA adducts formed by human exposure to 4-aminobiphenyl (4-ABP) during dye production, rubber-manufacturing processes and cigarette smoke. Accordingly, the ultrasensitive detection of ABP-derived adducts in DNA with minimal interference to the native structures becomes key for elucidating carcinogenesis mechanisms and mitigating the risk of cancer. In view of the lack of efficient optical emission in ABPG, we report a theoretical study on the photophysical properties of a set of quasi-intrinsic fluorescent C-analogues, which can form stable W-C base pairs with ABPG. It is found that fluorophore replacement and ring-expansion can bring a red-shifted absorption and bright photoluminescence due to additional π-conjugation. In particular, because the tricyclic cytosine analogue 1,3-diaza-2-oxophenoxazine (tCO) possesses distinct optical properties, it is proposed as a biosensor to identify ABPG. The TDDFT-calculated absorption maximum of tCO is red-shifted by 97 nm in comparison with that of the native C base, which contributes to selective excitation after incorporating into the nucleic acids. Although the fluorescence is insensitive to base pairing with natural guanine, the excited state intermolecular charge transfer (ESICT)-governed "OFF-ON" signal can be observed in the presence and absence of ABPG. Moreover, to evaluate the direct availability of the bright C-analogues with high selectivity for the deoxyguanosine adduct ABPG in DNA, we further investigated thoroughly the effects of its linking to deoxyribose on its absorption and emission, which shows little difference from that of experiment.

Regulation of various photo-active UOPs in a polymer matrix by tuning intermolecular charge transfer

Phosphorescent emitters, CzBN and CzPN, show intense UOP in PVA and PMMA matrices. The UOP performance in PVA matrices does not require a photo-active process, while different durations of photo-active process are required in PMMA.

Organic small molecular heterostructures for enhanced photocatalytic hydrogen evolutionviaisomer engineering

Organic small molecular photocatalysts with definite structures were developed by isomer engineering. The isomer regulation endows charge localization, enables fast intermolecular charge transfer and significantly different photocatalytic activity.

Electron density effect of aromatic carboxylic acids in naphthalenediimide-based coordination polymers: from thermal electron transfer and charge transfer to photoinduced electron transfer.

Various naphthalenediimide (NDI) based electron donor-acceptor coordination polymers (D-A CPs) have been constructed and used to explore charge transfer (CT) and electron transfer (ET) behaviors. Up to now, significant progress has been made in the interface contact and electron donor-acceptor ability matching mechanism, while the electronic density effect of the electron donors on the CT and ET behaviors is still not known. Herein, two NDI-based D-A CPs, [Cd2(H2NDI)(IPA)2(H2O)2] (1) and [Cd2(H2NDI)(IPA-OH)2(H2O)2] (2), are constructed using an NDI-based ligand and two aromatic carboxylic acid ligands (H2NDI = 2,7-bis(3,5-dimethyl) dipyrazol-1,4,5,8-naphthalene tetracarboxydiimide, H2IPA = isophthalic acid; and H2IPA-OH = 5-hydroxyisophthalic acid). UV-vis and EPR spectroscopy and DFT calculations analyses reveal that the occurrence of themal electron transfer (TET) in 1 and 2 results from the HOMO of the IPA and IPA-OH lying higher than the LUMO of the NDI. Meanwhile, compared to 1, the UV-vis absorption spectrum of 2 exhibits a significant red shift, which suggests higher electron density of the donor and more electron transfer pathways are beneficial for the occurrence of intermolecular CT. After UV light irradiation, the comparison of the photochromic behavior of 1 and 2 confirms the negative effect of the stronger CT on photoinduced electron transfer (PET). The present study illustrates the delicate modulating effect of electron density on the CT and ET behaviors in D-A CPs.

Molecular and Aggregate Structural, Thermal, Mechanical and Photophysical Properties of Long-Chain Amide Gelators Containing an α-Diketo Group in the Presence or Absence of a Tertiary Amine Group

Three structurally related gelators, each containing octadecyl chains, an α-diketo group at the 9,10 positions, and each with a different N-amide group-isobutyl (DIBA), isopentyl (DIPA) or N-(2-(dimethylamino)ethyl) (DMEA)-have been synthesized. Their neat structures as well as the thermal mechanical, and photophysical properties in their gel states with various liquids have been investigated. The gelator networks of DIBA and DIPA in octane, hexylbenzene and silicone oil consist of bundles of fibers. These gels are partially thixotropic and mechanically, thermally (to above their melting or silicone oil gelation temperatures), and photophysically stable. They are mechanically and thermally stronger than the gels formed with DMEA, the gelator with a tertiary amine group. The lone pair of electrons of the tertiary amine group leads to an intra-molecular or inter-molecular charge-transfer interaction, depending on whether the sample is a solution, sol, or gel. Neat, solid DMEA does not undergo the charge-transfer process because its amino and diketo groups are separated spatially by a large distance in the crystalline state and cannot diffuse into proximity. However, the solution of DIPA upon the addition of triethylamine becomes unstable over time at room temperature in the dark or (more rapidly) when irradiated, which initiates the aforementioned charge-transfer processes. The eventual reaction of the gelators in the presence of a tertiary amine group is ascribed to electron transfer from the lone-pair on nitrogen to an α-diketo group, followed by proton transfer to an oxygen atom on the anion radical of the α-diketo group from a methyl or methylene group attached to the nitrogen atom of the cation radical. Finally, the formation of an α-diketyl radical leads to irreversible electronic and structural changes that are observed over time.

Nonfused Dimethoxybenzene Electron Acceptors in Organic Solar Cells: From Molecular Design to Structure–Performance Relationship

The photovoltaic mechanism of asymmetric non-fullerene acceptors (NFAs) has not been sufficiently understood, although it is developing as a forceful method to design effective organic solar cells. This article systematically investigated and designed several configurations of nonfused acceptors at the micro level. Skeletons were constructed by a central 1,4-dimethoxybenzene core and flanked by different dithieno-pyrroles and thiophene derivates as electron-donating groups; the end-capped groups were composed of two 1,1-dicyanomethyl-3-indanone. Through theoretical calculation, one found that the designed DBPT series possessed narrower gaps, broadened the absorption to the near-infrared region, larger electron-accepting power, and separated the distance of holes and electrons. They also yielded enhancement mobility, which may relate to the significant dipole moment and electronic coupling. Furthermore, we constructed the device models by using PBDB-T as the donor. The heterojunction model results show that the optimized blends of PBDB-T/DBPT-4F achieved more intermolecular fragment charge amounts, more CT states, and smaller binding energy, showing a significant charge separation/recombination ratio. Then, under the macro-scale model, the device PBDB-T/DBPT-4F has a better power conversion efficiency of 14.69%, owing to a large simulated JSC of 18.82 mA cm–2, consistent with the trend of better interfacial transfer property. This work provided the global description of the molecular light response and the microscopic physicochemical mechanism of the intermolecular charge transfer process, which also sheds light on the structure–property relationship of unfused asymmetric NFAs and enables the strategy to develop valuable OSCs.

Computational investigation of tuning the electronic ability and featured for heterofullerene based dye sensitized solar cells

The structural characteristics of the heteroatom substituted fullerene to improve its physical and chemical properties are discussed in this work, highlighting possible applications in aromaticity, photocatalysis, solar cells, and superconducting materials. The energy gap of doped fullerene lowers significantly, making C31Nb a more reactive material and transforming it into an efficient superconductor. The molecular structure, energy and relative stabilities of the heterofullerene were examined and evaluated to determine the material's identification. According to the results analysis, the extra niobium atom and substituted carbon atom improve the electronic stability of heterofullerene. Using 13C NMR nuclear independent chemical shift, the stability of each fullerene and aromatic found in nature is discovered. Furthermore, the simulated infrared spectra of fullerene are reviewed, and the major distinctive peaks are given to different functional groups. NBO study which shows the intermolecular charge transfer from the donor to the acceptor in doped fullerene, demonstrates that the strong intermolecular contact between carbon and niobium atoms makes this material a notable material for NLO property.

A theoretical study on the effects of intramolecular and intermolecular interactions on excited state properties of two NIR-TADF combined with AIE molecules

TADF emitters with both high exciton utilization and luminescence efficiency show promising applications in OLEDs, especially it with AIE characteristics. However, theoretical studies on emitters with amorphous structure with the consideration of the solid-state effect are limited. In this work, a multi-scale simulation is performed to study the reported compounds TBSMCN and O-TBSMCN, which both possess distinct features of NIR-AIE-TADF. The packing modes of the molecules in film and crystal are obtained by molecular dynamics simulations (MD) and experiments, and then the photo physical properties are studied by using the QM/MM method. The results show that geometrical changes between the ground state (S0) and the first singlet excited state (S1) are restricted in aggregate state. Thus, the non-radiative energy consumption process is hindered, this indicates the AIE mechanisms. Second, the molecules exhibit a smaller △ES1-T1 and a more significant SOC in aggregate state, which is more favorable for the RISC. Finally, by analyzing the NTO of the dimers in the film, the O-TBSMCN molecule undergoes intermolecular charge transfer, which may be one of the reasons for the significant reduction in its film efficiency. Our calculations could help one to better understand the NIR-AIE-TADF mechanism from a theoretical perspective.

Electrokinetic, electrochemical, and electrostatic surface potentials of the pristine water liquid-vapor interface.

Although conceptually simple, the air-water interface displays rich behavior and is subject to intense experimental and theoretical investigations. Different definitions of the electrostatic surface potential as well as different calculation methods, each relevant for distinct experimental scenarios, lead to widely varying potential magnitudes and sometimes even different signs. Based on quantum-chemical density-functional-theory molecular dynamics (DFT-MD) simulations, different surface potentials are evaluated and compared to force-field (FF) MD simulations. As well explained in the literature, the laterally averaged electrostatic surface potential, accessible to electron holography, is dominated by the trace of the water molecular quadrupole moment, and using DFT-MD amounts to +4.35V inside the water phase, very different from results obtained with FF water models which yield negative values of the order of -0.4 to -0.6V. Thus, when predicting potentials within water molecules, as relevant for photoelectron spectroscopy and non-linear interface-specific spectroscopy, DFT simulations should be used. The electrochemical surface potential, relevant for ion transfer reactions and ion surface adsorption, is much smaller, less than 200 mV in magnitude, and depends specifically on the ion radius. Charge transfer between interfacial water molecules leads to a sizable surface potential as well. However, when probing electrokinetics by explicitly applying a lateral electric field in DFT-MD simulations, the electrokinetic ζ-potential turns out to be negligible, in agreement with predictions using continuous hydrodynamic models. Thus, interfacial polarization charges from intermolecular charge transfer do not lead to significant electrokinetic mobility at the pristine vapor-liquid water interface, even assuming these transfer charges are mobile in an external electric field.

Asymmetric intramolecular charge transfer enables highly efficient red thermally activated delayed fluorescent emitters

A feasible strategy of asymmetric donor–acceptor-second acceptor (D-A-A) structure is proposed for improving the photoluminecense (PL) and electroluminescence (EL) performance of red thermally activated delayed fluorescence (TADF) emitters. As a concept, four newly TADF emitters are designed and synthesized, D-A-A structure oTPAPO-DTPZ and pTPAPO-DTPZ and D-A-D type oDTPA-DTPZ and pDTPA-DTPZ, by using triphenylamine (TPA), dithieno[2,3-a:3′,2′-c]phenazine (DTPZ) and diphenylphosphine oxide (DPPO) groups as the donor, acceptor and second acceptor, respectively. It is demonstrated that abound intra- and inter-molecular CH···O hydrogen bonds are forming between TPA donor and DPPO acceptor for the asymmetric compounds, which effectively promote the intra- and inter-molecular charge transfer. Moreover, the steric hindrance of DPPO group availably suppresses the concentration quenching. As a consequence, the asymmetric D-A-A structured oTPAPO-DTPZ and pTPAPO-DTPZ exhibit relatively higher PL quantum yields and lower nonradiation rates, and thus better EL performance. In particular, device based on pTPAPO-DTPZ achieves the maximum luminance of 19360 cd m−2 and external quantum efficiency of 11.4 % at 632 nm, which are 2.3 and 1.5 times the values of pDTPA-DTPZ based device.

Influence of Intermolecular Packing on Light Emitting Efficiency and Carrier‐Mobility of Organic Semiconductors: Theoretical Descriptor for Molecular Design

AbstractIntegration of luminescence and carrier transport is of prime interest for optoelectronics, but full with challenges in organic semiconductors. Previously, it has been demonstrated that intermolecular charge transfer (ICT) in the herringbone H‐aggregate can lend oscillator strength to the lowest‐lying dark state if electron transfer (te) and hole transfer (th) integrals are in phase (same sign) and greater than , where J is exciton coupling. In this work, both herringbone and π–π stackings are considered and a universal descriptor is proposed. It is found that for π–π stacking with I > 1 and for herringbone with , respectively, the lowest dark state could become bright through mixing ICT component. Accordingly, it is found that eclipsed packing and use of molecules with acene‐like frontier molecular orbital profiles favor larger I value than the other packing patterns. Finally, with the help of the proposed descriptor, 13 high‐mobility emissive unit cores from 32 fused ring molecules are effectively screened out.

Hybrid Molecular Magnets with Lanthanide- and Countercation-Mediated Interfacial Electron Transfer between Phthalocyanine and Polyoxovanadate.

A series of {V12}-nuclearity polyoxovanadate cages covalently functionalized with one or sandwiched by two phthalocyaninato (Pc) lanthanide (Ln) moieties via V-O-Ln bonds were prepared and fully characterized for paramagnetic Ln = SmIII-ErIII and diamagnetic Ln = LuIII, including YIII. The LnPc-functionalized {V12O32} cages with fully oxidized vanadium centers in the ground state were isolated as (nBu4N)3[HV12O32Cl(LnPc)] and (nBu4N)2[HV12O32Cl(LnPc)2] compounds. As corroborated by a combined experimental (EPR, DC and AC SQUID, laser photolysis transient absorption spectroscopy, and electrochemistry) and computational (DFT, MD, and model Hamiltonian approach) methods, the compounds feature intra- and intermolecular electron transfer that is responsible for a partial reduction at V(3d) centers from VV to VIV in the solid state and at high sample concentrations. The effects are generally Ln dependent and are clearly demonstrated for the (nBu4N)3[HV12O32Cl(LnPc)] representative with Ln = LuIII or DyIII. Intramolecular charge transfer takes place for Ln = LuIII and occurs from a Pc ligand via the Ln center to the {V12O32} core of the same molecule, whereas for Ln = DyIII, only intermolecular charge transfer is allowed, which is realized from Pc in one molecule to the {V12O32} core of another molecule usually via the nBu4N+ countercation. For all Ln but DyIII, two of these phenomena may be present in different proportions. Besides, it is demonstrated that (nBu4N)3[HV12O32Cl(DyPc)] is a field-induced single molecule magnet with a maximal relaxation time of the order 10-3 s. The obtained results open up the way to further exploration and fine-tuning of these three modular molecular nanocomposites regarding tailoring and control of their Ln-dependent charge-separated states (induced by intramolecular transfer) and relaxation dynamics as well as of electron hopping between molecules. This should enable us to realize ultra-sensitive polyoxometalate powered quasi-superconductors, sensors, and data storage/processing materials for quantum technologies and neuromorphic computing.

Enhanced Selectivity in the Electroproduction of H2 O2 via F/S Dual-Doping in Metal-Free Nanofibers.

Electrocatalytic two-electron oxygen reduction (2e- ORR) to hydrogen peroxide (H2 O2 ) is attracting broad interest in diversified areas including paper manufacturing, wastewater treatment, production of liquid fuels, and public sanitation. Current efforts focus on researching low-cost, large-scale, and sustainable electrocatalysts with high activity and selectivity. Here a large-scale H2 O2 electrocatalysts based on metal-free carbon fibers with a fluorine and sulfur dual-doping strategy is engineered. Optimized samples yield with a high onset potential of 0.814 V versus reversible hydrogen electrode (RHE), an almost ideal 2e- pathway selectivity of 99.1%, outperforming most of the recently reported carbon-based or metal-based electrocatalysts. First principle theoretical computations and experiments demonstrate that the intermolecular charge transfer coupled with electron spin redistribution from fluorine and sulfur dual-doping is the crucial factor contributing to the enhanced performances in 2e- ORR. This work opens the door to the design and implementation of scalable, earth-abundant, highly selective electrocatalysts for H2 O2 production and other catalytic fields of industrialinterest.

A computational study of thiophene containing small-molecule electron acceptors for non-fullerene organic photovoltaic cells

During the past few years, researchers have devoted extensive efforts to improve organic solar cell (OSC) performance to reach interesting power conversion efficiencies (PCE) exceeding 10 %. Among heterojunctions OSCs (BHJ) types, Fullerene based small molecule acceptors (SMAs) have proved to be a favorable option in virtue of their high-power conversion efficiency (PCE), good electronic conductivity and superior charge segregation. Yet, they represent some serious limitations, such as low light absorption over 600 nm, solubility in organic solvents, and inefficient processing. Accordingly, the so-called non-fullerene acceptors (NFA) organic group was developed and showed excellent characteristics over fullerene acceptors with their easily tunable band gap, strong absorption in the visible region, low voltage loss, good morphological stability and simple fabrication techniques. In the present paper, a series of non-fullerene electron acceptors (C1–C4) were designed by modifying the reference material R. we have obtained new conjugated organic structures by adding more functional capped units. The quantum chemical study (DFT/TD-DFT) approach was used to perform theoretical calculations in order to characterize the effect of end group redistribution via the frontier molecular orbital (FMO), optical absorption, reorganization energy in accordance with R. Using PTB7-Th as an electron donor, open circuit voltage (Voc), photovoltaic properties and intermolecular charge transfer have been also calculated for all the conceived compounds. The findings revealed that all engineered materials (C1–C4) possess narrow band gap and great optical characteristics. In addition the proposed structures have displayed comparatively lower electron and hole reorganization energies, we have found that C1 represents the lowest electron and hole reorganization energies, respectively 0.048 eV and 0.028 eV, consequently the highest electron and hole mobility [1]. These interesting outcomes could prove proposed electron acceptors to be excellent candidates in the improvement of optoelectronic properties of organic solar cell technology.

Unveiling the inter-molecular charge transfer mechanism of N-doped graphene/carbon nanotubes heterostructure toward oxygen reduction process for Zn-air battery

Heteroatom-doped carbon-based materials have been deemed as highly efficient electrocatalysts for cathodic oxygen reduction reaction (ORR) in the sustainable energy conversion technologies. However, the limited active sites caused by the aggregation of carbon layers ineluctably hinder the mass transfer, thereby generating insufficient ORR performance. Herein, we offer a rational and facile method to manufacture a hybrid heterostructure of N-doped graphene and carbon nanotubes at the pyrolysis temperature of 900 °C (N-G/CNTs-900), which exhibits a better ORR activity than most of reported carbon-based ORR electrocatalysts, and comparable to that of Pt/C. Thus-fabricated N-G/CNTs-900 features hierarchically porous architecture, high specific surface area, abundant defects, and high active N content, and what’s more, it also affords active sites for oxygen activation and subsequent 4e− reduction processes due to the hetero-interlayer charge transfer and the electron accumulations of the carbon atoms on the surface layer by theoretical calculations. Compared with commercial Pt/C, N-G/CNTs-900-based Zn-air battery presents a higher peak power density (133.60 mW/cm2) and a larger specific capacity (707 mAh/gZn). This work provides a novel idea to design the high-efficiency and long-term durability ORR catalyst, which is benefit for boosting the commercial applications of metal-free carbon-based materials in the renewable energy conversion devices.

Effects of Atypical Hydrogen Bonds and π-π Interactions on Nonlinear Optical Properties: Dimers of Triangular Structures Based on Perylene, Naphthalene, and Pyromellitic Diimides.

Nonlinear optical (NLO) materials have become important materials in the field of high-speed optical devices due to the changes in light absorption and refraction caused by the photoelectric field. Compounds tend to exist as aggregates rather than single molecules, so intermolecular interactions are crucial to the nature of aggregates. Therefore, to study the effects of intermolecular interactions on nonlinear optical properties, we use a dimer simplified model and adopt the methods of controlling variables, which are the different intermolecular interactions resulting from the different stacking patterns of dimers based on the same monomer structures (2PMDI-1NDI and 2NDI-1PDI). It is found that compared with dimers involving π-π interactions, dimers involving C-H···O interactions have shorter intermolecular distances, larger intermolecular interaction energies, and smaller highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energy gaps. Moreover, the C-H···O interactions are more conducive to the intermolecular charge transfers and more beneficial for increasing the nonlinear optical response values of aggregates with respect to π-π interactions. This work provides an important basis for the influence of intermolecular interactions on nonlinear optical properties.

Optically active polymer charge‐transfer complex as a form of charge‐transfer chiralions

AbstractPoly(bis‐3,4‐ethylenedioxythiophene) was synthesized by electrochemical polymerization in cholesteric liquid crystal (Ch*LC) in the presence of 7,7,8,8‐tetracyanoquinodimethane (TCNQ). TCNQ acted as a supporting salt and a molecular dopant against the resultant poly(bisEDOT) to form a donor–acceptor‐type polymer charge‐transfer (CT) complex. Because a three‐dimensional (3D) one‐handed chiral structure was imprinted from the matrix chiral liquid crystal, the resulting polymer with TCNQ molecular doping displayed optical activity in the circular dichroism absorptions. This result indicates the production of optically active CT species comprising the polymer and the low‐molecular‐weight acceptor. The intermolecular chiral CT complex formed a one‐handed helical structure. This method is referred to as “CT complex liquid crystal (LC) electrochemical polymerization” to produce the helical polymer CT complex as atropisomers. Further, the optically active CT of the polymer is referred to as “CT chiralions.” The CT formation resulted from the molecular doping of TCNQ in the chiral polymer prepared in the helical LC matrix. As a result, molecular doping and molecular‐imprinting polymerization in the LC produced CT chiralions. The two‐step electrochemical polymerization in one‐pot polymerization developed in this study allowed the results to form a double‐layer fingerprint with a moiré‐like pattern.

Theoretical study on the electronic properties of different types of the donor:acceptor complexes

Non-fullerene organic solar cells can be classified into four forms in line with the different types of donor (D) and acceptor (A) in the active layer: all-polymer (PD:PA), polymer D:small-molecule A (PD:MA), small-molecule D:polymer A (MD:PA), and all-small-molecule (MD:MA). On the basis of having studied the electronic properties of a large number of related monomer molecules and D:A complexes, this work constructed four groups of D:A molecular pairs as described above as examples to investigate their electronic properties with first-principles density functional theory. The results show that the absolute value of the average binding energy of the PD:PA complex D18:P(NDI2HD-T) is larger than others, indicating the structure is relatively more stable. In accordance of the Bader charge analysis, the intra-molecular charge transfer of small-molecule is greater than polymers. For these blends, the intermolecular charge transfer of the all-polymer pair D18:P(NDI2HD-T) is larger, revealing that the PD:PA pair may result in a stronger intermolecular dipole electric field, which is beneficial to facilitate the separation of excitons. In addition, the MD:MA pair DRTB-T:FDICTF-2Cl and the PD:MA complex D18:FDICTF-2Cl all exhibit a larger amount of intra-molecular charge transfer, which indicates that the small-molecule acceptors in D:A complexes are conducive to promoting intra-molecular charge transfer.

D 6 h Symmetric Radical Donor–Acceptor Nanographene Modulated Interfacial Carrier Transfer for High-Performance Perovskite Solar Cells

<i>D</i> ^{6 <i>h</i>} Symmetric Radical Donor–Acceptor Nanographene Modulated Interfacial Carrier Transfer for High-Performance Perovskite Solar Cells

Heterocyclic chalcone derivatives with D-π-A framing modulated electronic, linear and nonlinear optical properties as effective candidates for nonlinear optical applications

Polarizability and hyperpolarizability values from the theoretical studies provided evidence that the material can be employed as an efficient nonlinear optical (NLO) material. The z-scan analysis reveals a good value for third order susceptibilities (χ3) in order of 10−6 esu and the optical limiting behavior shows a low optical limiting threshold, indicating suitability for nonlinear optical applications. Quantum chemical calculations give additional information on molecular structures, frontier orbitals, and global reactivity indices, allowing for a deeper understanding of the chalcone's electronic structure and properties. NBO computation revealed that extended hyperconjugation and strong intermolecular interactions are important for their structural stability as well as their contribution to NLO responses. Large dipole moment values, small HOMO-LUMO gap and Molecular Electrostatic Potential (MEP) surface analysis are evidence of intermolecular charge transfer (ICT) occurring within the molecules. Based on our experimental and theoretical results, we can conclude that the compounds under consideration have potential in NLO applications such as optical limiting devices.