Heats of mixing and the solid-state transition in [(C6H5)3PCH3]1– +x[(C6H5)3AsCH3] +x(TCNQ) –2, (0 ⩽×⩽ 1), anion radical salts

Abstract

The phase transitions of solid solutions were investigated with the anion radical salts of [(C₆H₅)₃PCH₃]_1–⁺_x[(C₆H₅)₃AsCH₃]⁺_x(TCNQ)^–_{[graphic omitted]}, (0 ⩽×⩽ 1). The behaviour of the phase transitions with respect to the composition parameter (x) was studied by using a regular binary solid solution model. It was found that the difference in the heats of mixing between the low-temperature (αγ) and high-temperature (βγ) phases of the solid solutions was very important in the explanation of the line shape of the observed phase diagram.