Inelastic neutron scattering spectra of free base and zinc porphines: a comparison with DFT-based vibrational analysis.
Inelastic neutron scattering spectra of free base and zinc porphines: a comparison with DFT-based vibrational analysis.
复制标题
游离碱和锌卟啉的非弹性中子散射谱：与基于 DFT 的振动分析的比较。
DOI：
10.1021/jp0507795
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
B. Hudson
中科院分区：
文献类型：
--
作者：
N. Verdal;P. Kozlowski;B. Hudson
用B3 LYP方法在6- 31 G（d）和6- 311 G（d，p）基组上计算了卟啉的非弹性中子散射（INS）谱，并与密度泛函理论（DFT）计算结果进行了比较.为了获得实验和理论之间的定量一致性，应用了两种不同的标度技术：为B3 LYP/6- 31 G（d）计算开发了标度量子力学（DFT-SQM）力场，并将均匀频率标度技术（DFT-UFS）应用于B3 LYP/6- 311 G（d，p）结果。DFT-SQM计算先前已经与IR和拉曼光谱进行了比较，具有良好的一致性，这使得几乎完整的振动分配。本研究的结果扩展了以前的振动分析的可靠性和复杂性更高的水平。先前的结果是增强的比较计算和观察到的INS强度和计算模式与INS光谱中观察到的，但以前未观察到的光谱的比较。INS光谱和两种计算的结果之间获得了很好的一致性，从而可以更详细和可靠地描述卟啉的振动性质。
Inelastic neutron scattering (INS) spectra of free base (FBP) and zinc (ZnP) porphines are presented and compared with the results of density functional theory (DFT) calculations using the B3LYP functional with 6-31G(d) or 6-311G(d,p) basis sets. To obtain quantitative agreement between experiment and theory, two different scaling techniques have been applied: a scaled quantum mechanical (DFT-SQM) force field was developed for B3LYP/6-31G(d) calculations and the uniform frequency scaling technique (DFT-UFS) was applied to B3LYP/6-311G(d,p) results. The DFT-SQM calculations have been previously compared with IR and Raman spectra with good agreement, which allows for a nearly complete vibrational assignment. The results of the present study extend previous vibrational analysis to a higher level of reliability and complexity. The previous results are augmented by the comparison of calculated and observed INS intensities and the comparison of calculated modes with those observed in INS spectra but previously unobserved in optical spectra. Excellent agreement is acquired between the INS spectra and the results of both calculations, permitting a more detailed and reliable description of the vibrational properties of porphyrins.