A set of exchange-correlation functionals, including BLYP, PBE0, B3LYP, BHandHLYP, CAM-B3LYP, LC-BLYP, and HSE, has been used to determine static and dynamic nonresonant (nuclear relaxation) vibrational (hyper)polarizabilities for a series of all-trans polymethineimine (PMI) oligomers containing up to eight monomer units. These functionals are assessed against reference values obtained using the Møller-Plesset second-order perturbation theory (MP2) and CCSD methods. For the smallest oligomer, CCSD(T) calculations confirm the choice of MP2 and CCSD as appropriate for assessing the density functionals. By and large, CAM-B3LYP is the most successful, because it is best for the nuclear relaxation contribution to the static linear polarizability, intensity-dependent refractive index second hyperpolarizability, static second hyperpolarizability, and is close to the best for the electro-optical Pockels effect first hyperpolarizability. However, none of the functionals perform satisfactorily for all the vibrational (hyper)polarizabilities studied. In fact, in the case of electric field-induced second harmonic generation all of them, as well as the Hartree-Fock approximation, yield the wrong sign. We have also found that the Pople 6-31+G(d) basis set is unreliable for computing nuclear relaxation (hyper)polarizabilities of PMI oligomers due to the spurious prediction of a nonplanar equilibrium geometry.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/jcc.23316 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
DFT-based calculation of vibrational sum frequency generation spectral features of crystalline β-sheets in silk: Polarization and azimuth angle dependences.
J Chem Phys
December 2024
Department of Chemical Engineering, Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Sum frequency generation (SFG) necessitates both noncentrosymmetry and coherence over multiple length scales. These requirements make vibrational SFG spectroscopy capable of probing structural information of noncentrosymmetric organic crystals interspersed in polymeric matrices and their three-dimensional spatial distributions within the matrices without spectral interferences from the amorphous components. However, this analysis is not as straightforward as simple vibrational spectroscopy or scattering experiments; it requires knowing the molecular hyperpolarizability of SFG-active vibrational modes and their interplay within the coherence length.
View Article and Find Full Text PDFStacking interactions in stabilizing supramolecular assembly of M[9C]M complexes: dynamic stability with remarkable nonlinear optical features.
Phys Chem Chem Phys
December 2024
Department of Physics, Government College of Engineering, Srirangam, Tiruchirappalli-620012, Tamilnadu, India.
Continual attempts have been made to discover excellent nonlinear optical (NLO) materials. Here, we investigate the role of stacking interactions and van der Waals forces in the designed parallel stacked complexes M[9C]M (where M = Li, Na, K, Be, Mg, and Ca) using various quantum chemical and molecular dynamics methods. The thermodynamic stability of the present complexes is also revealed by the computed interaction energy, enthalpy of formation, and Gibbs free energy of formation (Δ).
View Article and Find Full Text PDFGrowth of L-asparagine monohydrate organic single crystals: An experimental and DFT computational approach for nonlinear optical applications.
Heliyon
November 2024
Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh.
Good optical quality of L-asparagine monohydrate (CHNO.HO) organic single crystal has been grown by adopting natural slow evaporation process at room temperature from aqueous solutions. The lattice parameters obtained by powder X-ray diffraction data revealed orthorhombic crystal system of the harvested crystal.
View Article and Find Full Text PDFSolvent effect, DFT and NLO studies of A-π-D-π-A and A-π-D-π-D push-pull chromophore of 1,2-diazepin-4-ol based derivatives with optical limiting application.
Spectrochim Acta A Mol Biomol Spectrosc
January 2025
Department of Physics, St. John's College of Arts and Science, M.S. University, Kanyakumari 629204, Tamil Nadu, India.
The nonlinear optical properties of push-pull chromophores, namely (E)-7-(4-bromophenyl)-2,5-bis(4-nitrophenyl)-3,4,5,6-tetrahydro-2H-1,2-diazepin-4-ol (A-π-D-π-A) and (E)-7-(4-bromophenyl)-5-(4-nitrophenyl)-2-phenyl-3,4,5,6-tetrahydro-2H-1,2-diazepin-4-ol (A-π-D-π-D), have been investigated using the z-scan technique. NMR, FT-IR, and UV-visible spectral analysis have been performed. The results were compared with density functional theory calculations employing the B3LYP/6-311++G (d, p) basis set.
View Article and Find Full Text PDFSynthesis, crystal structure analysis, computational modelling and evaluation of anti-cervical cancer activity of novel 1,5-dicyclooctyl thiocarbohydrazone.
Phys Chem Chem Phys
September 2024
Department of Chemistry, University of Lucknow, Lucknow - 226007, Uttar Pradesh, India.
Thiocarbazones are widely used as bioactive and pharmaceutical intermediates in medicinal chemistry and have been shown to exhibit diverse biological and pharmacological activities such as antimicrobial, anticancer, anti-viral, anti-convulsant and anti-inflammatory In continuation of our interest in biologically active heterocycles and in an attempt to synthesize a spiro derivative, 1,2,4,5-tetraazaspiro[5.7]tridecane-3-thione, herein, the synthesis of 1,5-dicyclooctyl thiocarbohydrazone (3) has been reported reaction of the cyclooctanone and thiocarbohydrazide. The structure was assigned on the basis of detailed spectral analysis and also confirmed by X-ray crystal studies.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!