Structural modifications of Cu(II) 12-tungstophosphoric acid salt studied by IR and Raman spectroscopy

Abstract

In this paper local processes and structural phase transformations of the copper salt of 12-tungstophosphoric acid are investigated. The structural phase transformations were followed through bands, characteristic for the host lattice, in the IR and Raman spectra. The results of these investigations, as well as those of XRPD analysis and impedance measurements as a function of temperature show that some local processes provoke the change in the secondary structure of the Keggin anions.

U ovom radu ispitivani su lokalni procesi i strukturne fazne transformacije soli bakra 12-volframfosforne kiseline. Strukturne fazne transformacije praćene su preko traka karakterističnih za kristalnu rešetku u infracrvenim i ramanskim spektrima. Rezultati ovih ispitivanja, kao i oni dobiveni rendgeno-strukturnom analizom i iz impedansnih merenja, odnosno provodljivost u funkciji temperature, pokazuju da je fazna transformacija vezana za promene lokalne strukture, tj. sekundarne strukture Keginovih anjona. PR Projekat Ministarstva nauke Republike Srbije.