EPR Spectra of Some Cu2+-Doped Metal Carbonates and Disorder Phase Transition in K3H(Co3)2

Abstract

Cu2+-doped K<inf>3</inf>H(CO<inf>3</inf>)<inf>2</inf>, Rb<inf>2</inf>CO<inf>3</inf>, and Rb<inf>2</inf>KH(CO<inf>3</inf>)<inf>2</inf> single crystals were investigated by electron paramagnetic resonance (EPR) spectroscopy. The EPR spectrum of K<inf>3</inf>H(CO<inf>3</inf>)<inf>2</inf> indicates two different sites for Cu2+ at room and at low temperatures. But the signals for the two sites overlap at 318 K which is attributed to a disorder phase transition. Each of the other compounds exhibits one site. The Cu2+ ion seems to substitute the K+ and Rb+ ions and the charge compensations are fulfilled by the proton vacancies in K<inf>3</inf>H(CO<inf>3</inf>)<inf>2</inf>, and another K+ and Rb+ in the other compounds. The spin Hamiltonian parameters g and A for each compound are determined and discussed. © 2014, Verlag der Zeitschrift für Naturforschung. All rights reserved.