Manifestation of phase transitions in the crystal field spectra of [(CH3)2CHNH3]4Cd3Cl10:Cu crystals. (October 2018)

• Record Type: Journal Article
• Authors: Kapustianyk, V.; Yonak, P.; Rudyk, V.; Czapla, Z.; Podsiadła, D.; Eliyashevskyy, Yu; Kozdraś, A.; Demchenko, P.; Serkiz, R.
• Is Part Of: Journal of physics and chemistry of solids. Volume 121(2018)
• Page Start: 210
• Page End: 218
• Publication Date: 2018-10
• Subjects: Transition metal alloys and compounds -- Optical materials -- Optical spectroscopy -- Crystal and ligand fields -- Phase transitions; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2018.04.025
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: On the basis of absorption spectroscopy data the temperature evolution of the Cu 2+ ion environment in the crystal of [(CH3 )2 CHNH3 ]4 Cd3 Cl10 doped with Cu 2+ (IPACC:Cu) was studied. As it follows from the temperature dependences of heat capacity and absorption coefficient at a constant wavelength IPACC:Cu crystals are characterised by I order phase transitions at T 1 = 358 K and T 3 = 253 K whereas the continuous changes observed at T 2 = 293 K would be related to the first order phase transition close to the second order. For the detailed analysis of the crystal field spectra in the temperature range from T 3 till T 1 the special program package Crys Tool 2.0 based on the quantum mechanical models first of all on the model of normalized spherical harmonics (NSH) has been employed. It has been found that similarly to the crystal of ((CH3 )2 CHNH3 )4 Cd3 Cl10 (IPACC) the investigated doped crystal contains the distorted octahedral metal-halogen complexes of two types and the degree of their distortion is considerable changed in vicinity of the phase transition at T 2 = 293 K. The phase transitions at T 2 and T 3 were found to be shifted toward the low temperatures in comparison with initial IPACC crystal whereas the high temperature transition at T 1 is shifted to the higher temperatures. Highlights: Influence of Cu 2+ doping on phase transitions in [(CH3 )2 CHNH3 ]4 Cd3 Cl10 is studied. The phase transitions at T 2 and T 3 are shifted to lower temperatures. The high temperature transition at T 1 is shifted to the higher temperatures. The program package Crys Tool 2.0 based on the quantum mechanics was created. The doped crystal contains the distorted [CdCl6 ] complexes of two types.