Thermal stability, low gap energy and high Temperature order–disorder Phase Transition in Hybrid Material: [N (CH3)4]2PdCl4

• Published in: Applied organometallic chemistry 2020-04, Vol.34 (4), p.n/a
• Main Authors: Dakhlaoui, I., Karoui, K., Jomni, F.
• Format: Article
• Language: English
• Subjects: (TMA)2PdCl4; Band theory; Chemistry; Crystallization; Density functional theory; DSC, optical properties; Energy gap; High temperature; Optical properties; Palladium; Phase transitions; Raman spectra; Single crystals; Thermal stability; Unit cell; Vibrational spectra; vibrational spectroscopy and DFT
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.5545

The crystal compound [N (CH3)4]2PdCl4 was crystallized in the orthogonal system and the space group is P4/mmm and the refined unit cell parameters are a = b = 8.831 Å, c = 11.415 Å. The structure, vibrational spectra and optical properties have been investigated. DSC studies indicate the presence of two phase transitions at higher temperature which confirm the thermal stability of the palladium‐based compound. These transitions have been studied by Raman scattering on single crystals as a function of temperature which confirmed their nature. The assignment of the observed bands is discussed based in the theoretical calculated frequencies by the density functional theory (DFT) method using B3LYP/LanL2DZ basis in the GAUSSIAN‐09 package of programs. The optical properties in the UV–visible region have been deduced and the energy gap has been determined which is equal to 3.11 eV. The thermal stability and the reduction of the gap energy of the hybrid compound [N (CH3)4]2PdCl4 are compared with similar compounds based on other metals such as Zn, and Cu which are characterized by a gap energy greater than 5 eV and several phase transitions at low temperatures.