Conduction electron spin resonance measurements on TTF-TNNQ and (TMTTF)2BF4 under hydrostatic pressure

Abstract

Conduction electron spin resonance (CESR) measurements under hydrostatic pressure on two chain organic conductor tetrathiofulvalene-tetracyanoquinodimethane (TTF-TCNQ) and single chain organic conductor bis tetramethyl-tetrathiofulvalene borontetrafluorid ((TMTTF)2BF4) are presented. In both cases the CESR linewidth increases strongly with pressure in contradiction with the Elliott-mechanism for spin relaxation. The g-factor is pressure independent for both compounds while the spin susceptibility decreases by - 8 ± 1 %/kbar for TTF-TCNQ and - 3 ± 1 %/kbar for (TMTTF) 2BF4 at room temperature