The structure and two-dimensional correlation infrared spectroscopy study of a new 2D polyoxomolybdate complex containing β-octamolybdate linked up by potassium ions:: (4,4′-Hbpy)2(K2Mo8O26)

A novel compound, (4,4'-HbpY)(2)(K2Mo8O26) 1 (bpy = bipydine), was synthesized by hydrothermal method and characterized by X-ray single analysis, thermal gravimetric analysis, one-dimensional (ID) infrared spectroscopy and two-dimensional (2D) correlation infrared spectroscopy under thermal perturbation. In the compound 1, the [Mo8O26] units link to potassium ions to form layer structure, and the protonated 4,4'-bpy are linked to chains by hydrogen bonds. The 2D IR correlation spectroscopy study indicates that the intensity changes of Mo=O, N-H and C-C stretching vibration are sensitive to the temperature variation, and the intensity changes of asymmetry stretching vibration of the terminal Mo=O occur prior to that of terminal Mo=O linked by K atom. At the same time, the peaks of asymmetry stretching vibrations of the terminal Mo=O and the stretching vibrations of N-H split into two peaks respectively in 2D IR correlation spectroscopy. (c) 2005 Elsevier B.V. All rights reserved.