Shift In Absorption Spectra Research Articles

Spectra and Photorelaxation of Hydroxyphenyl-benzotriazole-Type UV Absorbers: From Monomers to Nanoparticles.

Water-insoluble organic UV filters such as 2,2'-methylene-bis-(6-(2H-benzotriazole-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol) (MBBT) can be prepared as aqueous dispersions of nanoparticles. The particles consist of the respective UV absorber molecules and show strong UV absorbance. Because there is a certain solubility of such UV absorbers in organic solvents, it is possible to measure the absorbance spectrum in solution also, for instance, in ethanol or dioxane. The UV spectrum of the aqueous dispersion shows a significant bathochromic shift of the long-wavelength band with an additional shoulder. For the understanding of the observed changes of UV-vis spectra of this UV absorber, either dissolved in an organic solvent or dispersed as nanoparticles in water, density functional theory (DFT) calculations were carried out with the respective monomer and aggregates of MBBT molecules in different media. The calculated UV-vis spectra of isolated, that means dissolved, MBBT molecules in ethanol and in dioxane agree well with the experimentally observed ones. The observed changes in the shape and position of experimental UV-vis spectra in aqueous dispersion cannot be explained with the solvent effect alone. It was found that the studied molecules could form stable energetically favorable π-stacked dimers, which show UV-vis spectra in reasonable agreement with those experimentally observed in aqueous dispersion. Such aggregates of MBBT are most likely the reason for the observed bathochromic shift in the UV-vis absorption spectrum. In addition, the mechanism of the photochemical deactivation of the excited MBBT molecules was studied in detail with time-dependent DFT in dioxane and in water. The energetically most favorable pathway for the deactivation of absorbed energy by MBBT occurs through intramolecular enol-keto tautomerization in the first excited singlet state.

Electronic and optical behaviour of lanthanum doped CaTiO3 perovskite

To improve the efficiency of perovskite based solar cells, doping of heavier elements in Perovskite materials (ABX3) can modulate its electronic and optical properties significantly. Thus it is important to understand the possible microscopic origin of the band gap modification and optical enhancement after heavier element doping using first-principles studies. Here we investigate the effect of La doping, while substituting the Ca atom, on the electronic and optical properties in CaTiO3 perovskite material using generalized gradient approximation within density functional theory. We observe a decrease in lattice constants and bond lengths in LaxCa1−xTiO3, mainly due to re-distribution of electronic charge density between La and Oxygen, as confirmed by charge density contour. We further notice a widening of electronic band gap and an upward shift of Fermi level into the conduction band, thus characterizing LaxCa1−xTiO3 as an n-type material. DOS diagram attributes this shift mainly due to the appearance of La p-DOS and d-DOS and their repulsion with N p-DOS, when La enters into the host lattice at Ca site. Investigation of optical properties upon La Doping in CaTiO3 exhibits further shifting of polarization and refractive index to lower values as compared to its pure counterpart, due to dominating semiconducting behavior and hence one observes a blue shift in absorption and reflection spectrum accordingly. Energy loss function is found to be consistent with absorption and extinction coefficient measured in case of LaxCa1−xTiO3. All these results are found to be consistent with the existing experimental and first-principles studies.

Electropolymerized poly(3,4-ethylenedioxyselenophene) on flexible substrate: A comparative study of electronic and electrochromic properties with sulfur analogue and rigid substrate

Recently, significant efforts have been devoted on poly(3,4-ethylenedioxyselenophene) (PEDOS) and its derivatives due to their promising properties for various optoelectronic applications. Surprisingly, no study has been reported on electrochemical synthesis of PEDOS on flexible substrate, and its optoelectronic properties. In this work, electropolymerization of 3,4-ethylenedioxyselenophene (EDOS) on flexible (ITO/PET) as well as rigid (ITO/glass) substrates, followed by cyclic voltammetry, electrochemical stability, morphology, spectroelectrochemical, and electrochromic properties of the PEDOS films were studied. For comparison purpose, poly(3,4-ethylenedioxythiophene) (PEDOT) films were also prepared on both flexible and rigid substrates and a throughout comparison was made. It has been observed that the polymer films on flexible substrates are relatively more stable, rough, and show blue shift in absorption spectra as compared to the polymer films on rigid substrates. On repeated bending, polymers films on flexible substrate exhibits good mechanical stability. Moreover, polymer film on flexible substrate has improved contrast ratio than that of polymer film on rigid substrate, whereas no significant change of response time has been observed. To the best of our knowledge, electropolymerization of EDOS on flexible substrate has been reported for the first time.

Isosbestic Point in Optical Mapping; Theoretical and Experimental Determination With Di-4-ANBDQPQ Transmembrane Voltage Sensitive Dye.

Optical mapping methods utilize fluorescence dyes to measure dynamic response of cardiac tissue such as changes in transmembrane potential (Vm). For the commonly used Vm sensitive dyes, a dye absorption and emission spectra shift as Vm changes. Signals relevant to Vm are calculated as a relative fluorescence change with respect to the fluorescence baseline. The amplitude of the change depends on the long-pass (LP) filter cut-on wavelength, placed on the sensor side, and the excitation wavelength. An excitation wavelength near the absorption peak, termed the isosbestic point, results in minimal absorption coefficient change as absorption spectra shifts. Consequentially the fluorescence intensity virtually does not change, when fluorescence across the entire emission spectra is measured, irrelevant of Vm changes. In this study we experimentally determined the isosbestic point for a near infrared dye Di-4-ANBDQPQ. We then present a theoretical study examining the dye linear or non-linear response as the fractional fluorescence change of Vm change, due to emission spectra shift and amplitude change, over a range of excitation wavelengths and LP filters. Linear "optical" response is important to quantify certain aspects of cardiac dynamics such as the action potential (AP) shape and duration, especially when studying drug effects and dynamical substrates for arrhythmia development.

DFT Calculation on the Electronic Structure and Optical Properties of InxGa1-xN Alloy Semiconductors

Using the density functional theory (DFT) of the first principle and Generalized gradient approximation method, the electronic structures and optical properties of the InxGa1-xN crystals with different x (x = 0.25, 0.5, 0.75, 1) have been calculated in this paper. The influence of the electronic structure on the properties has been analyzed. Then the influence of doping quantity on the characteristics has been summarized, which also indicates the trend of complex dielectric function, absorption spectrum and transitivity. With the increase of x, the computational result shows that the optical band gap (i.e.Eg) of the InxGa1-xN crystal tends to be narrow, then the absorption spectrum shifts to the low-energy direction. And the Fermi energy slightly moves to the bottom of conduction band which would cause the growth of conductivity by increasing x. In a word, the InxGa1-xN compound can be achieved theoretically the adjustable Eg and photoelectric performance with x, which will be used in making various optoelectronic devices including solar cell and sensors.

Synthesis and Optical Properties of Cubic Chalcopyrite/Hexagonal Wurtzite Core/Shell Copper Indium Sulfide Nanocrystals.

We report a synthetic method to produce heavy-metal-free heterophase core/shell CuInS2 nanocrystals, which comprise differently sized cores with a cubic chalcopyrite (CP) structure overgrown with hexagonal wurtzite (WZ) shells. For a given core size, CP/WZ core/shell CuInS2 nanocrystals experience shifts in both absorption and photoluminescence spectra toward the near-infrared with increasing shell thickness. Studies of the photoluminescence dynamics of these heterophase CuInS2 nanocrystals reveals behavior similar to that of the typical type II nanostructures constructed from different semiconductor materials of the same crystal structure. The interface between the CP core and the WZ shell has an important effect on the photoluminescence quantum yield.

Long-Range Self-Assembly of an Electron-Deficient Hexaazatrinaphthylene with Out-of-Plane Substituents.

The unprecedented time-dependent long-range supramol-ecular assembly of electron-deficient hexaazatrinaphthylene (HATN) core based on peripheral crowding with three out-of-plane cyclic ketals is reported. The single-crystal X-ray structure of the diethyl derivative provided detailed information as to how four molecules in a repeating unit were packed in order to avoid steric crowding of the out-of-plane cyclic ketal side chain, providing locking and fastening for stabilizing the self-assembled structure. The polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) did not instantaneously show any phase transition upon the cooling process. To our surprise, POM images showed a nucleation of spherulite up to 100 μm after 24 hour later. X-ray diffraction data further confirmed that these soft crystal formed a hexagonal-like crystal. The long-range self-assembly of the new material showed a slight red shift in the UV-vis absorption spectra and further substantiated by computational method.

SYNTHESIS AND SPECTRAL PROPERTIES OF BODIPY LUMINOPHORE WITH EXTENDED π-ELECTRONIC SYSTEM

We report the synthesis, purification and identification of a new derived class of BODIPY - of naphtho-fused BODIPY analogue, 8-(3,5-dimethylphenyl)-4,4-difluoro-4-bora-3a,4a-diaza-dinapht-[1,2b][1,2c]-s-indacene. A detailed method for obtaining the compound was given. The structure was confirmed by nuclear magnetic resonance spectroscopy, infrared spectroscopy and mass spectrometry. Electronic absorption and fluorescence spectra were obtained in solvents of different nature. The effect of solvent nature on the positions of absorption and fluorescence peaks and Stokes shift has been studied. It has been shown that the nature of the solvent has a significant effect on the fluorescence intensity and does not significantly effect the position of the absorption peaks. The photophysical characteristics of the compound were compared with known alkylated analogues. It is shown that the expansion of the electronic system leads to a bathochromic shift in the electronic absorption and fluorescence spectra. Quantum-chemical calculations of the electronic absorption and fluorescence spectra were carried out using the TDDFT (time dependent density functional theory) method. The influence of the extended π-electron system on the position and character of the absorption and fluorescence spectra was studied. It is shown that the presence of naphthalene fragments conjugated with the BODIPY core leads to a bathochromic shift of the absorption and fluorescence bands, as well as a partial change in the character of the spectra. The energy levels and electronic structure of the FMOs with the TDDFT method were calculated. The calculated data are in good agreement with the results obtained by experimental methods. The results obtained, in turn, are consistent with the results obtained earlier by our scientific group. Compounds that possess such properties are especially important and could be used in such practical applications as photovoltaics, photodynamic therapy of oncological diseases and as agents for visualization of biomolecules.

Curcumin/beta-cyclodextrin inclusion complex as a new “turn-off” fluorescent sensor system for sensitive recognition of mercury ion

The formation of supramolecular complex between the curcumin (CC or probe L) and β-cyclodextrin (β-CD) (CC: β-CD or probe LC) was confirmed using absorption and emission spectroscopy. The binding properties of probe LC with cations in water were observed for the first time via absorption and emission spectroscopies. The selectivity and sensitivity of fluorescence chemosensors have been studied using probe LC. The probe LC showed selective binding to Hg2+ and afforded new absorbance and fluorescence peaks at 379 nm and 502 nm, additionally to the prevailing bands of LC at 432 nm and 535 nm. It additionally showed apparent color change from yellow to colourlessness and strong fluorescent to weak fluorescent owing to selective binding of Hg2+ ion, which was detected by naked eyes. No noticeable changes of color and spectra were observed upon the addition of other metal cations such as [Ag+, K+, Na+, Cs+, Ba2+, Fe2+, Mg2+, Pb2+, Mn2+, Ni2+, Cd2+, CO2+, Cr3+, Sn2+ and Zn2+. Hg2+ produced blue shift in absorption spectra and quenching in emission spectra which suggested a likelihood of strong binding of Hg2+ ions with probe LC. The fluorescence response was concentration-dependent and can be well described by the typical Stern–Volmer model. Compared with prior reports, this method is very cheap, selective, sensitive and easily biodegradable of probe LC.

Спектральное и квантово-химическое изучение таутомерных и ионных превращений 2-(2-(2-гидрокси-5-сульфанилфенил) гидразон)-3-оксо-N-фенилбутанамида

In this paper, using the method DFT/B3LYP of quantum chemical modeling, the stability of tautomeric, conformer, and anionic forms of 2-(2-(2-hydroxy-5-sulfamoylphenyl)hydrazone-3-oxo-N-phenylbutanamide (H2L) was studied and the geometric, electronic structure and bond lengths of molecules in various tautomeric forms were determined. It was shown that the stability of tautomeric molecules H2L as anionic forms was determined by the number of existing intermolecular hydrogen bonds (closing six-membered and five-membered cycles). The most stable tautomeric and conformal forms of an organic molecule and its dianion are proposed. The interatomic distances, angles, charges on atoms, IR and electronic absorption spectra of tautomeric forms of the molecule and dianion (H2L and L2-) were calculated. In this work, we studied the electronic absorption spectra in an aqueous-alcoholic solution and found that in an alkaline medium the molecule transforms into the ionic form with a bathochromic shift of 47 nm, corresponding to the results of the shift of the long-wavelength band electronic absorption spectra upon transition from the hydrazotautomer (form a) to the dianion form (form b’’) at 92 nm obtained by TD-DFT. The calculated results for the distance and angles between atoms are in good agreement with the experimental data of the molecule by X-ray diffraction analysis. It was shown that the IR spectrum of the stable form appears two absorption bands in the region of 1690 and 1655 cm–1, which are attributed to stretching vibrations of carbonyl groups (C=O), bound by a strong intramolecular hydrogen bond and the presence of the NH-hydrazone fragment of the 1H NMR spectrum confirmed the most stable for a neutral molecule is the hydrazone form.

Synthesis and characterization of 1,2,3-triazoles-linked urea hybrid sensor for selective sensing of fluoride ion

Two urea-linked 1,2,3-triazole based sensors (5a and 5b) have been synthesized by 1,3-dipolar cycloaddition between 1-(4-fluorophenyl)-3-(prop-2-yn-1-yl)urea (2) and phenyl azides (4a-4b) via copper(I)-catalyzed click reaction. The synthesized sensors 5a and 5b have been evaluated for their sensing ability towards anions (F−, Br−, Cl−, I−, H2PO4− and AcO−) and cations (Cu2+, Zn2+, Ca2+, Co2+, Cd2+, Hg2+, Pb2+ and Ni2+) through UV–Visible, fluorescence and NMR spectral techniques. It was observed that sensor 5a exhibited selective sensing for F− ion with a bathochromic shift in absorption spectrum and showed fluorescence “turn-on” behaviour in the emission spectroscopy. The UV–Visible experiments exhibited that 5a interact with F− ion with a stability constant (K) of 2.058 × 104 M−1 and detection limit of 5a for F− ions was found to be 65.76 ± 0.45 μM. Furthermore, these results were also supported by density functional theory (DFT) calculations.

Auxiliary hydroxy-phenanthro [9, 10-d] imidazole supported NLOphoric triphenylamine based donor-pi-acceptor compounds: Synthesis, solvatochromism and computational aspects

To study the effect of additional hydroxy-imidazole unit on the solvatochromic linear, and non-linear optical properties, three donor-pi-acceptor NLOphoric triphenylamine-imidazole based compounds were synthesized, and characterized. The photophysical characteristics of the synthesized compounds were examined in series of solvents. The solvatochromism in the chromophores supported by the linear (i.e. Mac-Rae, and Lippert-Mataga equations) as well as by the multi-linear (i.e. Kamlet-Taft and Catalan parameters) analysis. ‘Solvent polarizability’ and ‘solvent dipolarity’ are the major components influence the shift in absorption and emission spectra respectively. These compounds exhibit aggregation induced emission. The charge transfer characteristics in the chromophores are examined with the Generalized Mulliken-Hush, molecular electrostatic potential, and Frontier molecular orbital plot analysis. The NLO properties of the synthesized compounds were studied using solvatochromic as well as computational methods. With the increase in the additional acceptor imidazole substituent on triphenylamine unit the polarizability, hyperpolarizability, and their associated molecular hyperpolarizability parameters gets enhanced.

Prediction of Absorption Spectrum Shifts in Dyes Adsorbed on Titania

Dye adsorption on metal-oxide films often results in small to substantial absorption shifts relative to the solution phase, with undesirable consequences for the performance of dye-sensitized solar cells and optical sensors. While density functional theory is frequently used to model such behaviour, it is too time-consuming for rapid assessment. In this paper, we explore the use of supervised machine learning to predict whether dye adsorption on titania is likely to induce a change in its absorption characteristics. The physicochemical features of each dye were encoded as a numeric vector whose elements are the counts of molecular fragments and topological indices. Various classification models were subsequently trained to predict the type of absorption shift i.e. blue, red or unchanged (|Δλ| ≤ 10 nm). The models were able to predict the nature of the shift with a good likelihood (~80%) of success when applied to unseen data.

Spectroscopic and photophysical properties of mono- and dithiosubstituted BODIPY dyes

A series of BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) dyes, substituted at the 3 and 5 positions was synthesized and their spectral and photophysical properties were investigated in solvents of different polarity and polarizability. All compounds are characterized by strong absorption bands at 500–580 nm, corresponding to S0 → S1 transition, the typical for the BODIPY chromophore. Emission spectra are mirror images to absorption with maxima at 520–600 nm. Substitution of the BODIPY chromophore by Cl or thioalkyl substituents induces batochromic shifts in both absorption and emission spectra for 50–60 nm and induces higher quantum yields of fluorescence (Φf = 0.1–0.7). The findings were rationalized by TD-DFT computations. The dyes exhibit weak solvatochromic properties which could not be correlated to solvent polarizability, contrary to majority of BODIPY derivatives. Furthermore, estimated singlet excited state lifetimes (τ = 2–6 ns) reveal that radiative and non-radiative rate constants for deactivation from S1 do not vary with changes in solvent polarity/polarizability. However, the highest values of Φf and τ are generally found in solvents of high polarizability. Presented spectroscopic and photophysical study is important for the use of dyes as chemodosimeters for thiols and cystein, as well as for the rational design of new molecular probes.

Second derivative analysis of synthesized spectra for resolution and identification of overlapped absorption bands of amino acid residues in proteins: Bromelain and ficin spectra in the 240-320 nm range.

We establish the origin and formation of peaks in UV absorption spectra of proteins by applying the second derivative analysis to (i) spectra of the native protein, (ii) to its model spectra "synthesized" as a sum of partial free amino acid spectra and (iii) to absorption spectra of the free amino acids. We show that the bromelain peaks at 248.2, 253.2, 258.4 and 264.2 nm are due to phenylalanine maxima; the predictable peak at 279.6 nm (which is almost coincident with the extremum of the zero-order spectrum at 279.4 nm) is mainly due to tyrosine maximum, while the peaks at 274.6 and 290.6 nm are due to tryptophan maximum; 268.0 nm peak to the superposition of tyrosine and phenylalanine maxima, and 283.4 nm peak to the superposition of tyrosine and tryptophan maxima. Similar results are obtained for ficin: the peaks at 248.4, 253.0 and 258.8 nm are formed by the phenylalanine maxima, the predictable peak at 264.4 nm accords with the corresponding bromelain 264.2 nm peak; the 279.4 nm peak almost coincides with the zero order spectrum peak (279.6 nm), but it is expressed stronger than that of bromelain due to a different ratio of tyrosine to tryptophan side groups. The peaks at 273.4 and 290.6 nm are associated with tryptophan, the 268.0 nm peak being mainly due to tyrosine (and fractionally to phenylalanine); and the 283.8 nm peak belongs to tyrosine and, to a greater extent, to tryptophan. We demonstrate that the amino acid residues of tryptophan, tyrosine and phenylalanine undergo correspondingly the largest, intermediate and the lowest positive (red) wavelength shift in the zero-order protein absorption spectrum with respect to the model (synthesized) spectrum. The difference appearing in the positions of the bromelain and ficin absorption band peaks is determined by superposition of relative contributions from amino acid residues. This superposition is resulted from (i) linear combination of amino acid residues spectra and (ii) their different (non-uniform) wavelength shifts as functions of microenvironment of these residues' chromophores. The proposed approach to the analysis of the protein absorption spectra with the help of "synthesized" spectra can be transferred to other objects studied in analytical and organic chemistry of high molecular compounds containing monomer units with various chromophores.

Quinoline-fused BODIPY with large Stokes shift as near-infrared dye for cell imaging

A new BODIPY dye was synthesized by fusing quinoline with BODIPY core by oxidative cyclodehydrogenation reaction, and the spectral properties of this dye were investigated. It displayed remarkable red shift in absorption and emission spectra compared with its precursor. Especially, the maximum emission peak of the fused dye reached to the near-infrared region. The red-shifted spectrum was ascribed to the expansion of molecular electron system. Meanwhile, due to the reduction of molecular symmetry, the quantum yield of the fused dye in dichloromethane was 41% and Stokes shift was 67 nm. Moreover, the results of cell imaging showed that the fused dye could be a candidate chromophore in organisms due to its good imaging effect, high photostability and low cytotoxicity. In addition, the fused dye exhibited a quantum yield of 0.12 in solid state.

TCF-imidazo[1,5-α]pyridine: A potential robust ratiometric fluorescent probe for glutathione detection with high selectivity

A novel fluorescent probe, TCF-IPY, has been designed and developed for highly selective and ratiometric detection of GSH based on the extend of the π-conjugation system of imidazo[1,5-α]pyridine IPY-CHO. Upon addition of GSH, TCF-IPY displayed remarkable fluorescence variations (approximate 949-fold ratio changes) from 603 nm to 475 nm, thereby enabling GSH detection in a fine ratiometric manner. Moreover, TCF-IPY exhibited excellent selectivity toward GSH over other biologically related species including Cys and Hcy. The huge blue shifts both in absorption (259 nm) and emission spectra (128 nm), low cytotoxicity, high sensitivity (97 nM) and rapid response (240 s) of TCF-IPY make it a robust molecular tool for endogenous GSH investigation. Furthermore, TCF-IPY was also successfully used for ratiometric imaging of endogenous GSH in living MCF-7 cells and zebrafish.

Optical detection of a subatomic particle with an ultrahigh-resolution carbon sensor

Neutron detection finds wide use in various areas, thus the improvement of the relevant instruments and methods has been focused on for a long time. For the purpose of detecting possible neutrons, in the present paper, we theoretically put forward a carbon nanotube (CNT) sensor based on a single nitrogen-vacancy center coupled to a current-carrying CNT to detect neutrons. With two lasers applied, the accreted mass landing on the nanotube may cause a frequency shift in the probe absorption spectrum. Once the frequency shift is measured, the added mass will be determined. Through the use of this sensor, owing to the small effective mass and high quality factor of the CNT, an ultrahigh mass resolution could be achieved. Due to its ultrahigh resolution, the sensor can be used to detect neutrons. Furthermore, we provide a brand new optical approach for neutron detection.

Tuning the Optical Properties of Novel Antitumoral Drugs Based on Cyclometalated Iridium(III) Complexes.

Most of the current efforts in drug discovery are devoted to the design of molecules able to mitigate side effects by concentrating the biological action in the targeted tissue. One promising strategy is photodynamic therapy, which is based on the in situ generation of reactive singlet oxygen upon radiation exposure. However, such an approach requires the use of an efficient photosensitizer. This contribution deals with the optical properties of an Ir(III) complex, [Ir(pbz)2(N^N)] (pbz = 2-phenylbenzimidazole; N^N = methyl 1-butyl-2-pyridyl-benzimidazole-5-carboxylate), which has recently been shown to exhort a strong photoactivity, but still needs further improvements to reach clinical applications. We performed density functional theory calculations at the M06, PBE0, ωB97xD, and CAM-B3LYP levels to predict the impact of introducing electron donor-acceptor groups into the nature of the lowest excited states. The simulations performed demonstrate that the presence of a NH2 at the pbz ligand and a NO2 group at the N^N ligand yield a bathochromic shift of absorption spectrum. We report the most sensitive positions to tune the optical signatures of this family of complexes.

Pyrene Based NLOphoric D‐π‐A‐π‐D Coumarin‐Chalcone and Their Red Emitting OBO Difluoride Complex: Synthesis, Solvatochromism, Z‐scan, and Detailed TD‐DFT Studies

AbstractNLOphoric D‐π‐A‐π‐D coumarin chalcone 5 and their BF2 complex 6 were designed, synthesized and characterized through Mass,13C‐NMR, and 1H‐NMR analysis. Their Photophysical properties are extensively studied in solvents of different polarity. On BF2 complexation of coumarin chalcone shows highly red shift in absorption and emission spectra compared to uncomplexed coumarin chalcone. Positive solvatochromism observed which is well supported by linear and multilinear regression analysis. For BF2 complexed coumarin‐chalcone 6 the solvent dipolarity (CSdP) is the main factor responsible for slightly red shift in absorption spectra, and also for the highly red‐shift in emission spectra. Frontier molecular orbital, molecular electrostatic potential and Generalized Mulliken‐Hush analysis revealed intramolecular charge transfer in these compounds. Nonlinear optical (NLO) properties for compounds 5 and 6 were studied by solvatochromic and computational method. The linear polarizability (α), first‐order hyperpolarizability (β) and second‐order hyperpolarizability (γ) of compounds were studied by the time dependent density functional theory using three different functionals namely B3LYP, BHHLYP and CAM−B3LYP with the 6–31 G (d) basis set. BF2 complexed compound 6, show higher values for αe + αv as well as βe+βv compared to compound 5. Third order nonlinear optical susceptibility (χ(3)) of these compounds obtained by Z‐scan analysis. Third‐order (χ(3)) non‐linear optical properties of BF2 complexed coumarin‐chalcone 6 were observed to be several times higher than those of the uncomplexed coumarin‐chalcone 5 these justify the design approach.