A Quantum Chemical Study of Bonding Interaction, Vibrational Frequencies, Force Constants, and Vibrational Coupling of Pyridine−Mn (M = Cu, Ag, Au; n = 2−4)

• DOI: 10.1021/jp034951l
• Publication Date: 2003-11-06T13:53:23Z
• Authors: D. Y. Wu; M. Hayashi; Y. J. Shiu; K. K. Liang; C. H. Chang; Y. L. Yeh; S. H. Lin
• Keywords: Lone pair; Rotational–vibrational coupling

The binding interactions between the pyridine and small noble metal clusters in different sizes (n = 2−4) have been investigated by using quantum chemical methods. energies of Py−M2 complexes are obtained at levels Hartree−Fock method (HF), second-order Møller−Plesset perturbation theory (MP2), local density functional (SVWN), nonlocal (BLYP, BPW91, G96LYP, G96PW91), hybrid (B3LYP B3PW91). All calculated results show that bonding is stronger pyridine/copper pyridine/gold than pyridine/silver. mechanism explored terms molecular orbital properties. donation interaction lone-pair electrons on nitrogen molecule to unoccupied each cluster plays an important role. force constants internal coordinates interests presented. vibrational frequency shift has analyzed basis coupling modes nitrogen−metal stretching as well metal−metal modes. For low-frequency Raman spectra pyridine−small silver complexes, we propose a new assignment N−Ag Ag−Ag vibrations. infrared intensities compared with experimental spectra.