ESR Study of (C_5H_{12}N)_2CuBr_4

Abstract

ESR studies at 9.27, 95.4, and 289.7 GHz have been performed on (C${}_5$H${}_{12}$N)${}_2$CuBr${}_4$ down to 3.7 K. The 9.27 GHz data were acquired with a single crystal and do not indicate the presence of any structural transitions. The high frequency data were collected with a polycrystalline sample and resolved two absorbances, consistent with two crystallographic orientations of the magnetic sites and with earlier ESR studies performed at 300 K. Below $B_{C1}=6.6$ T, our data confirm the presence of a spin singlet ground state.

2 pages, 4 figs., submitted 23rd International Conference on Low Temperature Physics (LT-23), Aug. 2002