Rocha Mariana, Di Santo Alejandro, Arias Juan Marcelo, Gil Diego M, Ben Altabef Aída
INQUINOA, CONICET, Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, T4000CAN Tucumán, Argentina.
INQUINOA, CONICET, Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, T4000CAN Tucumán, Argentina.
Spectrochim Acta A Mol Biomol Spectrosc. 2015 Feb 5;136 Pt B:635-43. doi: 10.1016/j.saa.2014.09.077. Epub 2014 Sep 30.
The experimental and theoretical study on the molecular structure and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde (DMABA) is presented. The IR and Raman spectra were recorded in solid state. Optimized geometry, vibrational frequencies and various thermodynamic parameters of the title compound were calculated using DFT methods and are in agreement with the experimental values. A detailed interpretation of the IR and Raman spectra of the title compound were reported. The stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using NBO analysis and AIM approach. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and some molecular properties such as ionization potential, electron affinity, electronegativity, chemical potential, hardness, softness and global electrophilicity index. The TD-DFT approach was applied to assign the electronic transitions observed in the UV-visible spectrum measured experimentally. Molecular electrostatic potential map was performed by the DFT method. According to DSC measurements, the substance presents a melting point of 72.34°C and decomposes at temperatures higher than 193°C.
本文介绍了对4-（二甲基氨基）苯甲醛（DMABA）分子结构的实验和理论研究以及一种新的振动分析。以固态记录了红外光谱和拉曼光谱。使用密度泛函理论（DFT）方法计算了标题化合物的优化几何结构、振动频率和各种热力学参数，计算结果与实验值相符。报道了对标题化合物红外光谱和拉曼光谱的详细解释。使用自然键轨道（NBO）分析和分子中的原子（AIM）方法分析了由超共轭相互作用和电荷离域引起的分子稳定性。利用最高占据分子轨道（HOMO）和最低未占据分子轨道（LUMO）分析来确定分子内的电荷转移以及一些分子性质，如电离势、电子亲和势、电负性、化学势、硬度、软度和全局亲电性指数。应用含时密度泛函理论（TD-DFT）方法对实验测量的紫外可见光谱中观察到的电子跃迁进行归属。通过DFT方法绘制了分子静电势图。根据差示扫描量热法（DSC）测量，该物质的熔点为72.34°C，在高于193°C的温度下分解。
