Order Nonlinear Optical Material Research Articles

DFT insights into the nonlinear optical properties of azulene-stilbene dyads for photonics and optoelectronics

The present study aims to investigate the nonlinear optical characteristics of a series of azulene-stilbene chromophores through the utilization of density functional theory (DFT). Various acceptor substitution techniques were used to enhance first, second, and third order static and dynamic polarizabilities of the parent azulene-stilbene dyad (AS). The natural transition orbitals and UV-Visible absorption spectra were analyzed using time dependent-density functional theory (TD-DFT). Theoretical computations were performed to analyze the structural, electronic, and charge transfer properties of all designed compounds. The energy gap separating the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of the designed moieties was observed to decrease in the new compounds compared to the parent compound. Analysis of the nonlinear optical (NLO) data among the designed compounds (AS1-AS10) revealed that AS2, AS3, AS4, and AS10 exhibit promising second and third order NLO characteristics, with AS6 exhibits suitability as a second order NLO material and AS8 and AS9 display third order NLO responses. The computed static and dynamic NLO parameters and maximum absorption wavelength closely match the experimentally reported data in the literature, suggesting these derivatives are excellent candidates for photonic and optoelectronic applications in the future.

Non-Linear Optical Activity of Chiral Bipyrimidine-Based Thin Films.

An original series of bipyrimidine-based chromophores featuring alkoxystyryl donor groups bearing short chiral (S)-2-methylbutyl chains in positions 4, 3,4 and 3,5, connected to electron-accepting 2,2-bipyrimidine rings, has been developed. Their linear and non-linear optical properties were studied using a variety of techniques, including one- and two-photon absorption spectroscopy, fluorescence measurements, as well as Hyper-Rayleigh scattering to determine the first hyperpolarizabilities. Their electronic and geometrical properties were rationalized by TD-DFT calculations. The thermal properties of the compounds were also investigated by a combination of polarized light optical microscopy, differential scanning calorimetry measurements and small-angle X-ray scattering experiments. The derivatives were found not to have mesomorphic properties, but to exhibit melting temperatures or cold crystallization behavior that enabled the isolation of well-organized thin films. The nonlinear optical properties of amorphous or crystalline thin films were studied by wide-field second harmonic generation and multiphoton fluorescence imaging, confirming that non-centrosymmetric crystal organization enables strong second and third harmonic generation. This new series confirms that our strategy of functionalizing 3D organic octupoles with short chiral chains to generate non-centrosymmetric organized thin films enables the development of highly second order nonlinear optical active materials without the use of corona-poling or tedious deposition techniques.

A comprehensive study on synthesis, growth and characterization of Guanidinium 4-chloro-3-nitrobenzoate monohydrate (G4C3NBM) single crystal for NLO applications: A third order nonlinear optical material

The growth of guanidinium and benzoic acid based single crystal Guanidium 4‑chloro-3-nitrobenzoate monohydrate (G4C3NBM) was carried out via the process of slow evaporation using mixed solvents (water and ethanol). G4C3NBM crystals were obtained and multiple characterization techniques have been taken into consideration. To ascertain G4C3NBM crystal's structure, Single Crystal X-ray Diffraction (SXRD) study was performed and thereby cell parameter values were computed. The crystalline nature of G4C3NBM was elucidated by Powder X-ray Diffraction (PXRD) study. Fourier Transform Infrared Spectroscopy (FTIR) study was executed to know the vibrational assignments of G4C3NBM crystal. The linear optical properties of G4C3NBM crystal were investigated through UV–visible–NIR analysis. In addition, Photoluminescence (PL) spectra exhibited the emission characteristics of the crystal. The thermal stability of G4C3NBM was probed by utilizing TGA -DTA study. The Nd-YAG Laser (1064 nm) was employed to assess target crystal's Laser Damage Threshold (LDT) and a comparison was performed with other similar NLO crystals. The mechanical nature and various mechanical parameters were determined with the help of Vickers's Micro Hardness Test. A Z-Scan method was put to use to delve into the third order nonlinearities of G4C3NBM crystal and computations of all the related parameters were carried out. The promising results of the above studies and work performed indicate the excellent potential possessed by Guanidinium 4‑chloro-3-nitrobenzoate monohydrate (G4C3NBM) crystal for use in NLO applications.

Electronic Structure Modulation of Nanographenes for Second Order Nonlinear Optical Molecular Materials.

Nanographenes (NGs) have drawn extensive attention as promising candidates for next-generation optoelectronic and nonlinear optical (NLO) materials, owing to its unique optoelectronic properties and high thermal stability. However, the weak polarity or even non-polarity of NGs (resulting in weak even order NLO properties) and the high chemical reactivity of zigzag edged NGs hinder their further applications in nonlinear optics, thus stabilization (lowering the chemical reactivity) and polarizing the charge distribution in NGs are necessary for such applications of NGs. The fusion of heptagon and pentagon endows the azulene with the character of donor-acceptor, and the B=N unit is isoelectronic to C=C unit. The introduction of polar azulene and BN are idea to polarize and stabilize the electronic structure of NGs for NLO applications. In the present review, a survey on the functionalization and applications of NGs in nonlinear optics is conducted. The engineering of the electronic structure of NGs by topological defects, doping and edge modulation is summarized. Finally, a summary of challenges and perspectives for carbon-based NLO nanomaterials is presented.

The search for a maximum of the D-π-A paradigm for second order nonlinear optical molecular materials.

Push-pull π-conjugated molecules are one of the paradigms of second order nonlinear optical (NLO) materials and have been extensively explored. However, high-performance second order NLO materials with an optimum electron donor (D), π-bridge (π) and acceptor (A) under this paradigm are still the most sought-after. In the present work, D-π-A molecules with optimal D, π and A combination for strong second order NLO properties are proposed based on molecular orbital theories. The optimal D-π-A push-pull molecule achieves an unprecedentedly strong NLO response under the D-π-A paradigm, i.e., the static first hyperpolarizability reaches -453.92 × 10-30 esu per heavy atom using azulene as part of the π-bridge and acceptor to synergistically reinforce the strength of the acceptor. The protocols of D-π-A NLO molecule design through frontier molecular orbital matching of D, π and A with optimal combination of electron donating and accepting strengths shed light on future molecular NLO materials exploration. The simulated two-dimensional second order spectra provide useful information (e.g., sum frequency generation) on the applications of those D-π-A push-pull molecules in nonlinear optics.

Transition metalides based on facially polarized all-cis-1,2,3,4,5,6-hexafluorocyclohexane - a new class of high performance second order nonlinear optical materials.

Continuous attempts are being made to discover new approaches to design materials with extraordinary nonlinear optical responses. Herein, for the first time, we report the geometric, electronic, and nonlinear optical properties of novel Janus transition metalides AM-J-TM (where AM = Li, Na and K, and TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) containing alkali metals as a source of excess electrons for transition metals to generate metalides. The Janus organic complexant used for the study is all cis 1,2,3,4,5,6-hexafluorocyclohexane F6C6H6 (J). These complexes contain the unique involvement of alkali metals (AM = Li, Na and K) as a source of excess electrons, which significantly affects the hyperpolarizability values of the resulting transition metalides. The NBO analysis reveals the charge transfer from alkali metals to the transition metals, thereby confirming the metalide behavior of the complexes. Moreover, the metalide nature of these complexes is validated through frontier molecular orbital (FMO) analysis. The values of interaction energies, vertical ionization potential (VIP) and vertical electron affinity (VEA) illustrate the stability of the metalide complexes. Ultimately, the hyperpolarizability values confirm the excellent nonlinear optical response of the designed transition metalides. The remarkable static first hyperpolarizability (β0) response up to 4 × 108 a.u. is observed for complexes of vanadium. Similarly, the complexes of AM-J-Mn and Li/Na-J-Sc show significantly high NLO response. These compounds besides providing a new entry into excess electron compounds will also pave the way for the design and synthesis of further novel NLO materials.

Investigation on structural, theoretical, optical, vibrational, morphological, crystalline nature and nonlinear optical properties of propanone 2,4-dinitrophenyl hydrazone (PDNPH)

A dynamic third order nonlinear optical material “Propanone-2,4-dinitrophenyl hydrazone” (PDNPH) for optoelectronic appliances was harmonized at room temperature and single crystals were fully-fledged by Low Temperature solution Growth Technique. The structural framework of the fully fledged crystal specimen was analyzed by Single crystal X-ray Diffraction (SXRD) analysis. The fully fledged organic Propanone-2,4-dinitrophenyl hydrazone (PDNPH) single crystal was crystallized in Triclinic P-1 space group. Powder X-Ray Diffraction (PXRD) was implemented to reveal the crystalline phase of the material. The FTIR spectroscopy reveals the presence of molecular footprint present in the crystalline sample. The optical transmittance in the whole visible region was examined within the range of 200–800 nm. The morphology of PDNPH crystal was analyzed by using Scanning Electron Microscope. The elemental quantification for the grown PDNPH crystal was obtained by energy dispersive X-ray (EDX) spectroscopy. The self-defocusing of the crystal specimen was scrutinized by Z-scan technique. The non-linear refractive index, non-linear absorption coefficient and third order non-linear susceptibility for different planes of the PDNPH crystals were also attained. Quantum Chemical calculations were performed by using Gaussian 09 Suite and the theoretical values are reported. HRXRD reveals better crystalline nature of the grown specimen. The calculated HOMO and LUMO energies designate that charge transfer occurs within the molecule.

Effect of shock wave on optical properties of Propyl p-hydroxybenzoate single crystal: A self-defocusing third order nonlinear optical material

This work focuses on the effect of shock wave on optical properties of propyl p-hydroxybenzoate single crystal. An optically transparent single crystal was grown by adopting slow evaporation solution growth technique (SEST). Its structure was confirmed by powder X-ray diffraction using Reitveld refinement. The Hirshfeld surface morphology and the intermolecular interaction of titled compound was scrutinized using crystal explorer. Three shock waves generated at constant air compressor pressure of 0.78 Mpa with calculated Mach number 1.7 were allowed to interact with the grown crystal. The UV–vis spectroscopy analysis on shock wave treated sample shows an increase in transmittance for 1st and 2nd shock and a reduction of transmittance for the 3rd shock wave. The defects induced after each shockwave – sample interaction was investigated by photoluminescence spectroscopy and surface morphology studies in detail. The third order nonlinear properties like self – defocusing and reverse saturation absorption of grown crystal were studied using a femto-second Ti-sapphire laser source. The nonlinear absorption coefficient, refractive index were calculated to be 4.04 ˟ 10−10 cm/W and −8.47 ˟ 10−15 cm2/W using open and closed aperture Z-scan measurement respectively.

Structure, hirshfeld surface studies, optical and mechanical analysis on a third-order nonlinear optical crystal 2-amino-6-methylpyridin-1-ium 2-chloro-4-nitrobenzoate (2A6M2C4N)

Organic third order nonlinear optical material, 2-Amino-6-methylpyridin-1-ium 2-chloro-4-nitrobenzoate (2A6M2C4N) was effectively synthesized and single crystals were developed by slow cooling solution growth method. The crystallographic structure of the grown crystal has been confirmed through single crystal X-ray diffraction analysis and it uncovers that the title material belongs to Triclinic crystal system with centrosymmetric space group of P-1. The crystalline phase formation was ascertained from powder X-ray diffraction measurements. The functional groups present in the compound were confirmed by Fourier transform infrared analysis. Optical analysis explicit that the grown crystal possess good transmittance in the wave length region of 200–800 nm. Photoluminescence spectroscopy analysed by exciting the material at 320 nm supports that 2A6M2C4N crystal suits the requirements of optoelectronic devices. The thermal behaviour of 2A6M2C4N exploited by TG-DTA measurements show that it is stable up to 160.04 °C. Third order nonlinear optical properties such as nonlinear refractive index and third order nonlinear optical susceptibility were calculated by employing the z-scan technique. The HOMO-LUMO, molecular electrostatic potential (MESP) and contour map of the molecule was examined at B3LYP/6–311++G (d, p) level by using DFT calculations. The existence of the intermolecular interactions in the molecule were confirmed by Hirshfeld surface studies. • Novel third order nonlinear optical crystals 2A6M2C4N has been grown by slow cooling technique. • 2A6M2C4N belongs to triclinic crystal system with centrosymmetric space group P-1. • Intermolecular-interactions in 2A6M2C4N molecule were characterized by Hirshfeld surface analysis. • Third order nonlinear optical susceptibility (χ(3)) was calculated to be 2.918 × 10–11 esu.

Growth, characterisation and DFT investigations on 3-hydroxy-6- methyl -2- nitropyridine (3H6M2NP)-A novel third order nonlinear optical material

Single crystals of nitropyridine derivative 3-hydroxy-6-methyl-2-nitropyridine was grown by slow evaporation solution growth technique using ethanol. 3H6M2NP was crystallized in orthorhombic crystal system with centrosymmetric space group Pbca. The crystalline nature, presence of functional groups and its vibrational modes were assigned using FT-IR and FT-Raman spectroscopic techniques. The UV–Vis spectrum reveals 3H6M2NP crystal is transparent in the visible region with lower cut-off wavelength. The luminescence properties were confirmed by PL spectrum and 3H6M2NP crystal exhibited thermal stability up to 182 °C. The molecular structure of 3H6M2NP was optimised and all ab initio calculations were done theoretically. From Z-scan technique, the third order nonlinear optical susceptibility of the grown crystal was found to be χ3 = 2.616 × 10−8 esu. The hyper polarizability value was found to be 2.9 times larger than that of the urea which settles the NLO activity.

Comments on the paper “Insight on the growth and property studies of inorganic hydrated borate (Na6[B4O5(OH)4]3·8H2O) single crystal ̶ An effective third order nonlinear optical (NLO) material for optical limiting application”

The authors of the title paper (Mater. Chem. Phy. 205 (2018) 138–146) claimed to have grown for the first time a new alkali metal borate with formula Na6[B4O5(OH)4]3·8H2O (I) by slow evaporation of an aqueous solution containing NaOH, H3BO3 and C3H4O4 in 3:1:1 mol ratio. In this letter to the Editor, many points of criticism concerning the crystal growth, structure characterization and interpretation of the spectral and thermal data of I are described to prove that it is improperly characterized.

Synthesis and Controllable Growth Dynamics of Third Order Nonlinear Optical Material of 2-Amino-4-Methylpyridinium 2-Chloro 4-Nitro Benzoate Electro-Mechanical Investigation and Device Fabrication

An organic nonlinear optical material 2-Amino-4-methylpyridinium 2-chloro 4-nitro benzoate (AMPCNB) was synthesized and large size single crystals were grown by slow evaporation solution growth method. Single crystal X-ray diffraction study showed that the title compound belongs to monoclinic crystal system with P21/n space group. A powder XRD study was performed to ascertain its phase. The UV–VIS-NIR study was performed to investigate the transparency window and lower cutoff wavelength of the compound, no absorption has been observed between 318 and 1100 nm. The third harmonic efficiency of the title compound has been studied using the Z-scan technique using continuous-wave Nd:YAG laser to confirm its saturable absorption and self-defocusing effect. The photo conducting and charge transport properties are analyzed using photoconductivity and dielectric measurements. Theoretical calculation of molecular polarizability, which is helpful in device fabrication, was carried out from Penn gap, Clausius-Mosotti equations and the obtained results were compared. Mechanical properties of the grown crystal were investigated by Vicker’s microhardness study.

Linear–nonlinear optical and quantum chemical studies on Quinolinium 3,5-dinitrobenzoate: A novel third order non-linear optical material for optoelectronic applications

An organic non-linear optical (NLO) crystal of Quinolinium 3,5-dinitrobenzoate (DNBAQ) was synthesized and good quality single crystals of DNBAQ were grown by conventional slow evaporation solution growth technique. Single crystal XRD was utilized to confirm the formation of the charge transfer complex. The crystalline property and the presence of required functional groups was verified employing Powder XRD and FTIR spectral analysis. UV–Vis–NIR and Fluorescence study was performed to determine the optical transmittance and the emission property of the grown crystal. The thermal, mechanical and surface damage threshold stability of the complex was analysed using thermal studies, Vicker’s micro hardness studies and Laser damage threshold measurement. The solid state parameter of electronic polarizability of DNBAQ compound was computed through dielectric studies. The non-linear optical characterizations like Kurtz Perry powder technique and Z-Scan technique ensures the non-linear optical activity of the compound. The frequency conversion efficiency of the grown crystal was estimated to be 70% that of the standard Potassium Dihydrogen Phosphate (KDP). Z-Scan analysis confirms the suitability of the grown crystal for optical limiting and switching applications. Quantum chemical studies were adopted on the optimized geometry of DNBAQ molecule using Density Functional Theory (DFT). Frontier Molecular Orbital (FMO) analysis and Molecular Electrostatic Potential (MEP) analysis were performed. The non-linear optical behaviour of the complex was established by evaluating dipole moment, polarizability and hyperpolarizability features. All the above results confirm the resourceful candidature of DNBAQ material for optoelectronic and photonic applications.

Synthesis, growth and characterization of 2,5 – dimethyl-N-(3-phenylprop-2-en-1-ylidene) aniline (2,5 DPPA) single crystal: A new second order nonlinear optical material for photonic and optoelectronic applications

The second order nonlinear optical material and the single crystal of 2,5-Dimethyl-N-(3-phenylprop-2-en-1-ylidene) aniline (2,5 DPPA) which is organic in character was well synthesised by the standard slow evaporation method. The crystalline structure of 2,5 DPPA studied by single crystal XRD analysis confirmed that the material belongs to the orthorhombic crystal system with non-centrosymmetric space group P212121. Functional groups were analyzed by Fourier transforms infrared analysis. The calculated optical band gap was found to be 2.76 eV. The second harmonic generation of 2,5 DPPA crystal was confirmed by Kurtz–Perry powder test using the source of Nd:YAG laser and found that it is 1.25 times greater than that of reference KDP material. Thermal stability of the titled crystal was studied by TGA/DTA technique. The Vicker’s hardness (Hv) test portrays that the mechanical resistance of the crystal’s hardness coefficient value is 2. The dielectric constant and dielectric loss of the grown crystal decreases with increase in array of the line of value of the frequencies.

Synthesis, growth, thermal, mechanical and optical studies of piperazinium based cupric sulfate (PCS) single crystals: A third order nonlinear optical material

A third order nonlinear optical (NLO) good quality Piperazinium based cupric sulfate (PCS) single crystals has been grown successfully from homogeneous solution by slow evaporation technique using double distilled water at room temperature. The average dimensions of the as grown crystals are up to 36×30×15mm3 within a period of 35 days. The grown single crystals were subjected to powder X-ray diffraction (XRD) to confirm the crystalline quality. Single crystals X-ray diffraction represents, the PCS crystal belongs to the monoclinic system (P), with unit cell parameters a=6.87Å, b=10.20 Å, c=11.92Å and V=834A°3. Existence of major functional groups in PCS single crystal has been identified by FTIR analysis. The thermal properties of PCS single crystals were analyzed from TG−DTA curves and the compound is thermally stable up to 134°C. The UV–vis absorption studies indicate the PCS single crystals are optically transparent up to 60.88% at 496nm with the cut-off wavelength 258nm. From the Tauc's plot optical band gap is estimated to be (Eg)5.30eV.The extinction coefficient (k) vs. wavelength relation for PCS single crystals have minimum absorption of light around 493nm. The refractive index (n0) of PCS single crystals has least value for blue and green light; it is gradually increased till red light. It is supported by reflectance vs. wavelength calculation with high reflectance at same wavelength range. The photoluminescence (PL) emission spectra for as grown crystals represent prominent emission around 440−470nm depicting blue emission with 244nm excitation wavelength. The electric field response of PCS single crystals has been studies in terms of dielectric constant and dielectric loss as a function of frequency and temperature, the results were discussed. The mechanical stability of the grown crystals at room temperature has investigated with Vicker's micro hardness test and evaluated various mechanical parameters such as Hv,Kc,σv andC11.Hardness number increased with load.PCS single crystals exhibits RISE behavior and belong to soft category. The third order nonlinear optical nature of PCS single crystals was studied using Z−scan technique. The negative nonlinear refractive index (n2) of the crystals indicates self-defocusing effect. The nonlinear absorption coefficient (β) and third order nonlinear optical susceptibility (χ(3)) were also calculated and discussed from the above technique.

Synthesis, growth and characterization of guanidinium hippurate monohydrate single crystals: A new third order nonlinear optical material

Abstract Single crystals of a novel organic nonlinear optical (NLO) material-guanidinium hippurate monohydrate (GuHM) -are grown using slow evaporation solution growth technique. GuHM is an anion-cation system to which water molecules are attached by hydrogen bonding. The lattice parameters and crystalline purity of the crystal have been measured using single-crystal and powder X-ray diffraction (XRD) methods. Quantum chemical calculations using density functional theory (DFT) have been employed to calculate the vibrational modes and the first and second hyperpolarizabilities. Thermogravimetric (TG) and differential thermal (DT) analyses were carried out to characterize the thermal behaviour of the grown crystals. The role of intramolecular charge transfer and hydrogen bonds in making the molecule NLO-active are interpreted on the basis of the hyperpolarizability values. Along with DFT calculations, the natural bond orbital (NBO), the Atoms In Molecules (AIM), and the Hirshfeld surface imply the presence of a strong intra- and intermolecular N–H….O and O–H….O hydrogen bonding interactions between the charged species of GUHM crystal. The third-order optical nonlinearity of the crystal was studied using open-aperture Z-scan technique. From the experimental and theoretical data, it is concluded that GuHM is a potential NLO material.

Third order nonlinear optical property of WSe2 nanofilm at 800 nm

A tungsten selenide (WSe2) nanofilm was successfully prepared by liquid phase exfoliation. Open and closed aperture Z-scan techniques were used to distinguish between the real and imaginary parts of the third-order optical nonlinearity of the WSe2 nanofilm at 800 nm. The WSe2 nanofilm exhibits excellent saturable absorption characteristics at this waveband. A saturation light intensity of 147 ± 9 GW/cm2, a modulation depth of 24% and a nonlinear refractive index coefficient of about −1.36 × 10−10 cm2/W were obtained. The results reveal that the WSe2 nanofilm is an excellent third order nonlinear optical material, and has potential applications ranging from ultrashort pulse laser mode-locking to optical Kerr-based photonic devices in the 800 nm wavelength range.

Growth, experimental and theoretical investigations on 4-hydroxy-3-methoxybenzaldehyde 5-chloro-2-hydroxybenzoic acid: A new high second order nonlinear optical material

Novel 4-hydroxy-3-methoxy benzaldehyde 5-chloro-2-hydroxybenzoic acid (4H5C) organic co-crystal was grown by simple solution growth technique. 4H5C crystal exhibits the orthorhombic structure with non-centrosymmetric space group of Pna21 from single crystal X-ray diffraction study results. The cut-off wavelength and optical excitation wavelength was evaluated by using UV–Visible and PL spectral studies to the 4H5C heterodimer and suitability for the NLO applications are discussed. 4H5C single crystal material thermal stability and decomposition states were examined by using TG-DSC analysis. Vickers microhardness test was carried out on the flat surface of 4H5C crystal to understand the mechanical strength and behavior for weight loadings. Chemical etching patterns of 4H5C crystal surface was carried out and found the layer growth pattern. The second harmonic generation (SHG) efficiency of 4H5C single crystal was evaluated by Kurtz-Perry powder technique and result is compared with KDP crystal SHG efficiency. Polarizability, first order hyperpolarizability, geometric parameters of 45HC were evaluated theoretically by using B3LYP, CAMB3LYP methods of density functional theory by using 6-311++G (d,p) basis set. It is estimated that, the polarizability (3.38 x 10−23 e.s.u) and first order hyperpolarizability (9.370 x 10−30 e.s.u.) to the 4H5C heterodimer in B3LYP method.

A long-chain based bromo and methyl substituted chalcone derivatives; experimental and theoretical approach on nonlinear optical single crystals

In the present work, growth of single crystals of chalcone derivatives {4-[(1E)-3-(4-methylphenyl)-3-oxoprop-1-en-1-yl]phenyl 4-methylbenzene-1-sulfonate} (4M1PMS) and {4-[(1E)-3-(4-bromophenyl)-3-oxoprop-1-en-1-yl]phenyl4-methylbenzene-1-sulfonate} (4BPMS), at room temperature is reported. The spectroscopic techniques are used to identify the presence of functional groups in the materials. The single-crystal XRD and powder XRD analysis reveals that 4M1PMS belongs to non-centrosymmetric () and 4BPMS belongs to centrosymmetric crystalline system. The molecular structures exhibit C–H…O and π...π intermolecular interactions. From UV/VIS/NIR spectroscopic studies, it is found that both samples have bathochromic shifts in linear absorbance (cut-off region) spectra. The broad emission region involved in several sharp emission peaks in blue region, exhibits a blue light emission property, as observed from photoluminescence study, in both the samples. The thermal stability of the materials were studied by TGA/DTA techniques and crystals were thermally stable until the melting point. In NLO study, 4M1PMS crystal has shown SHG efficiency 2.2 times that of KDP crystal. In addition, electronic contribution in hyperpolarizability (first order and second order) tensors of both the compounds were computed theoretically by M06-2X functional at DFT level. The open/closed aperture Z-scan technique were performed to evaluate third order nonlinear optical materials by measuring experimental parameters such as nonlinear absorption/refraction and calculate second-order hyperpolarizability with corresponding third-order nonlinear optical susceptibility of 4M1PMS and 4BPMS. The surface damage threshold studies of 4M1PMS and 4BPMS were performed by Q-switched Nd:YAG laser at 532 nm.

An analysis of spectroscopic, computational and biological activity studies of L-shaped sulfamoylbenzoic acid derivatives: A third order nonlinear optical material

The current article focuses mainly on investigation of structural, reactivity, topology studies, and third order nonlinear optical properties of the synthesized 2-(benzylamino)-4-chloro-5-sulfamoylbenzoic acid (BACSBA) with the aid of spectroscopic techniques and computational methods. The structure in the solid state was obtained unambiguously by SCXRD study that revealed that BACSBA has L-shaped structure stabilized by N–H⋯O intramolecular hydrogen bond. Further, the two dimensional sheet like architecture formation by linking of molecules via O–H⋯O and N–H⋯O hydrogen bonds, were visualized both qualitatively and quantitatively by Hirshfeld surface analysis. Also, a topological analysis made through Quantum Theory of Atoms In Molecules (QTAIM) highlights the observations N–H⋯O bonds on solid state. The quantum chemical calculation was performed at DFT/6–311++G (d,p) level of basis set. The analysis of each vibrational wave number was performed with the help of potential energy distribution (PED) using VEDA4 software and correlation with experimental data shows good concurrence. The reactive sites have been predicted and visualized by molecular electrostatic surface potential (MESP) and Fukui function calculation, together with hydrogen bond dissociation energy (H-BDE) for the BACSBA compound. Frontier molecular orbitals (FMO), global reactivity parameters, natural bond orbital analysis (NBO), localized orbital locator (LOL) and electron localization function (ELF) properties have also been studied for the titled compound. The super molecule (SM) approach with 372,680 atoms at the DFT/CAM-B3LYP/6–311++G (d,p) level was used for calculating the nonlinear optical properties of the crystal. The electrical parameters such as total dipole moment, average linear polarizability and average second IDRI hyperpolarizability were calculated. In addition, the linear refractive index and the nonlinear third order macroscopic susceptibility of the crystal was estimated as a function of the frequency of the applied electric field. The value of third order nonlinear susceptibility for the BACSBA crystal at 532 nm was found to be 45.57 times greatest than the experimentally measured result of organic crystal (2E)-1-(3-bromophenyl)-3-[4 (methylsulfanyl)phenyl]prop-2-en-1-one (3Br4MSP) demonstrating that BACSBA crystal could be a good potential candidate for nonlinear optical applications. In addition, the thermal stability was studied showing that the crystal as potential optical devices at temperature up to 234 °C. Furthermore, preliminary studies revealed that BACSBA compound displayed promising antifungal and antioxidant activities compared with the standard drugs.