Significant studies of anilines reported biological activities like oxidation, polymerization, arylation, alkylation, protonation, conformation for photophysical and electrochemical properties using experimental and computational studies like CNDO, MINDO, PCILO that arise due to charge transfer interaction. These interactions still provide enough scope with analysis using electron density method to determine physical, chemical and electrooptical properties. The present work attributes family of anilines-aniline(AN), p-chloroaniline(CAN) and p-nitroaniline(NAN) with experimental studies like FTIR and FT Raman and Computational studies with Gauss View4.1 package using B3LYP–basis set 6-311++(d, p) for electrooptical properties. Interpretation of experimental spectra of FTIR and FT Raman confirm the wave numbers are in specified range corresponding to functional group and fingerprint regions. It is observed that intensity of the wave numbers in Raman spectra are reduced in comparison with infrared spectra. Molecular structures are visualized with molecular editor Avogadro for molecular properties. Computational studies are performed for optimized structures wherein the computed infrared spectra and Raman spectra are in agreement with experimental spectra. Studies of charge transfer interactions determine properties like dipole moment, EHomo, ELumo, energy gap, electrophilicity index, polarization and first order hyperpolarizability. A feature of work is NAN possess greater tendency in charge transfer interaction with reduced energy gap, high polarizability and first order Hyperpolarizability that enable to form complex for optical materials and devices.

No abstract

Dynamics of molecular structures has its dependence on symmetry, topological defects, responsibility to shear, short range interatomic forces, interplay of thermal and potential energies in formation of supramolecular structures with mesophase. Computational studies emerged as sophisticated tool that deliver the functional aspects responsible in formation of these molecular structures. The article attempts induced textures and phase transition studies of synthesized compound from anilines and aldehydes. Infrared spectral studies infer shits in wavenumbers in formation of secondary aldemines with anilines and aldehydes. Polarizing optical microscope and differential scanning calorimetric studies were performed for observation of textures and confirmation of transition temperatures. Computational studies were performed for these compounds responsible for induced phases using 6-311++(d,p) with quantum mechanical descriptors. Studies revealed that reduced energy gap and high dipole moment is consequence of change in order of transition in synthesized compound responsible for induced phase.

Characterization of materials infer for physical and chemical properties that depend on its molecular structure. Structure of molecule has its dependence on respective electrons of molecule under consideration occupying their positions that correspond to changes in density of electrons. Many theories of its kind were developed to study density of electrons with roots from wavefunction method and electron density method. Wavefunction method has its dependence with linear combination of atomic orbitals, Born approximation, variational principle ,potential energy surfaces for development of Huckel theory, Hartree fock self-consistent theory. Electron density method includes Ab-intio method and density functional theory is possible with Kohenberbg-Kohn existence theorem and Kohn Sham formalism. Density functional studies has diverted attention of researches for properties dependent on structure with use of quantum mechanical descriptors that influence chemical reactivity of molecule forming complexes with properties responsible for electrooptical activity. In the present work complexes with p-anisaldehyde were studied with set of anilines using Gaussian 16 package with B3LYP method. Studies in present work were analyzed from computed infrared spectra responsible for formation of complexes with shifts in wavenumbers; quantum mechanical descriptors for electronic properties. A feature of study is that complexes with p-nitroaniline have greater tendency influence on electronic properties responsible for electrooptical activity due to electrophilic nature.