Arockia doss M, Savithiri S, Rajarajan G, Thanikachalam V, Saleem H
Department of Chemistry, Annamalai University, Annamalainagar 608 002, India.
Department of Chemistry, Annamalai University, Annamalainagar 608 002, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2015 Sep 5;148:189-202. doi: 10.1016/j.saa.2015.03.117. Epub 2015 Apr 3.
The structural and spectroscopic studies of 3t-pentyl-2r,6c-diphenylpiperidin-4-one semicarbazone (PDPOSC) were made by adopting B3LYP/HF levels theory using 6-311++G(d,p) basis set. The FT-IR and Raman spectra were recorded in solid phase, the fundamental vibrations were assigned on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method and PQS program. DFT method indicates that B3LYP is superior to HF method for molecular vibrational analysis. UV-vis spectrum of the compound was recorded in different solvents in the region of 200-800 nm and the electronic properties such as excitation energies, oscillator strength, wavelengths, HOMO and LUMO energies were evaluated by time-dependent DFT (TD-DFT) approach. The polarizability and first order hyperpolarizability of the title molecule were calculated and interpreted. The hyperconjugative interaction energy (E((2))) and electron densities of donor (i) and acceptor (j) bonds were calculated using NBO analysis. In addition, MEP and atomic charges of carbon, nitrogen and oxygen were calculated using B3LYP/6-311++G(d,p) level theory. Moreover, thermodynamic properties of the title compound were calculated by B3LYP/HF, levels using 6-311++G(d,p) basis set. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results.
采用B3LYP/HF水平理论，使用6-311++G(d,p)基组对3t-戊基-2r,6c-二苯基哌啶-4-酮半卡巴腙（PDPOSC）进行了结构和光谱研究。在固相中记录了傅里叶变换红外光谱（FT-IR）和拉曼光谱，基于用缩放量子力学（SQM）方法和PQS程序计算的振动模式的总能量分布（TED）对基本振动进行了归属。密度泛函理论（DFT）方法表明，在分子振动分析方面，B3LYP优于HF方法。在200-800nm区域内，在不同溶剂中记录了该化合物的紫外可见光谱，并通过含时密度泛函理论（TD-DFT）方法评估了激发能、振子强度、波长、最高占据分子轨道（HOMO）和最低未占据分子轨道（LUMO）能量等电子性质。计算并解释了标题分子的极化率和一阶超极化率。使用自然键轨道（NBO）分析计算了超共轭相互作用能（E((2))）以及供体（i）和受体（j）键的电子密度。此外，使用B3LYP/6-311++G(d,p)水平理论计算了分子的分子静电势（MEP）以及碳、氮和氧的原子电荷。此外，使用B3LYP/HF水平，采用6-311++G(d,p)基组计算了标题化合物的热力学性质。通过规范无关原子轨道（GIAO）方法计算了该分子的(1)H和(13)C核磁共振（NMR）化学位移，并与实验结果进行了比较。
