Magnetic susceptibility of (VO)2P2O7: A one-dimensional spin-1/2 Heisenberg antiferromagnet with a ladder spin configuration and a singlet ground state

Abstract

Powder magnetic susceptibility data between 1.3 and 350 K are presented for the orthorhombic compound (VO${)}_2$ ${\mathrm{P}}_2$ ${\mathrm{O}}_7$, containing a one-dimensional ladder configuration of spins (1/2). Perhaps surprisingly, the data are accurately fitted, both as to shape and magnitude, by theoretical predictions of Bonner, Blöte, Bray, and Jacobs for the spin-(1/2) alternating antiferromagnetic Heisenberg chain, with $J_1$/$k_B$=-65.7 K, $J_2$/$k_B$=-46.0 K, and g=2.00, where $J_1$ and $J_2$ are the two alternating exchange-interaction constants and g is the Landé g factor.