V-H-2 Temperature Dependence of Crystal Structures, and Electrical Conducting and Magnetic Properties in Plate Crystals of 1:2 Tetrafluorotetracyanoquinodimethane/Tetra-fluorotetracyano-quinodimethanide Mixed Tetramethyl-ammonium and -Phosphonium Salts

Kazumasa UEDA (Osaka Pref. Univ.), Toyonari SUGIMOTO (Osaka Pref. Univ. and IMS), Toshiharu TADA, Kei-ichiro NISHIMURA, Satoshi ENDO, Naoki TOYOTA, Masakado KOHAMA, Koji YAMAMOTO (Osaka Pref. Univ.), Toshiyuki YAMAGUCHI, Yusaku SUENAGA, Megumu MUNAKATA (Kinki Univ.), Nobuko KANEHISA, Yoshiyuki SHIBAMOTO, Yasushi KAI (Osaka Univ.) and Nobuyoshi HOSOITO (Kyoto Univ.)

[Mol. Cryst. Liq. Cryst. 296, 323 (1997)]

The room-temperature crystal structure of a plate of (PMe₄⁺·TCNQF₄^-·)·1/2TCNQF₄ was analyzed (Figure 1) and very similar to that of the corresponding NMe₄⁺ salt. However, significant difference was recognized between the two crystals in the structures of TCNQF₄ and TCNQF₄^-· molecules, and in the contacts between the dimerized TCNQF₄^-· molecules and between the TCNQF₄ and TCNQF₄^-· molecules. The change in both molecular structure and contact as above was also observed at a lowering temperature. The magnitude in change was larger in the NMe₄⁺ salt than in the PMe₄⁺ salt. However, such a change in the crystal structure by temperature exerted no special influence on the electrical conducting and magnetic properties.

Figure 1. The room-temperature crystal structure of a plate of (PMe₄⁺TCNQF₄^-·)·1/2TCNQF₄.

back to CONTENTS of Research Activities V