Magnetic Susceptibility of Quasi-One-Dimensional Compoundα'-NaV2O5–Possible Spin-Peierls Compound with High Critical Temperature of 34 K–

Stoichiometric powder samples of α'-NaV 2 O 5 were synthesized and the magnetic susceptibility was measured in the temperature range from 2 K to 700 K. The magnetic susceptibility has a good fit to the equation for an S =1/2 antiferromagnetic Heisenberg linear chain with J / k B =280 K and g =2 above 34 K. Below 34 K the magnetic susceptibility rapidly decreases with decreasing temperature to a constant value of 1.49×10 -4 emu/V 4+ -mol which is reasonable for spin-singlet V 4+ –V 4+ pairs. This rapid reduction of the spin susceptibility below 34 K suggests the existence of a spin-Peierls transition. α'-NaV 2 O 5 is a possible spin-Peierls compound with the highest critical temperature yet observed.