1:2 TCNQ/TCNQ −. mixed salts exhibiting ferromagnetic behavior at room temperature

Abstract

Ferromagnetic behavior at room temperature was observed in the tetramethylammonium (NMe + 4) and cesium (Cs +) salts of tetracyanoquinodimethane (TCNQ) and its radical anion (TCNQ −.) in a molecular ratio of 1:2. The saturation magnetizations and coercive forces are 0.79 emu/mol and ≈300 Oe for ( NMe + 4 · TCNQ −.) · 1 2 TCNQ , and 1.46 emu/mol and ≈100 Oe for ( Cs +. · TCNQ −.) · 1 2 TCNQ , respectively. In contrast, the 1:1 TCNQ/TCNQ −. mixed tetraethylammonium (NEt 4 + salt, (NEt 4 +·TCNQ −·)·TCNQ, exhibited no ferromagnetic behavior at room temperature nor at lower temperatures.