Dynamical properties of the spin-Peierls compound α'--NaV2O5

Abstract

Dynamical properties of the novel inorganic spin-Peierls compound α'--NaV2O5 are investigated using a one-dimensional dimerized Heisenberg model. By exact diagonalizations of chains with up to 28 sites, supplemented by a finite-size scaling analysis, the dimerization parameter δis determined by requiring that the model reproduces the experimentally observed spin gap Δ. The dynamical and static spin structure factors are calculated. As for CuGeO3, the existence of a low energy magnon branch separated from the continuum is predicted. The present calculations also suggest that a large magnetic Raman scattering intensity should appear above an energy threshold of 1.9 Δ. The predicted photoemission spectrum is qualitatively similar to results for an undimerized chain due to the presence of sizable short-range antiferromagnetic correlations.

4 pages, latex, minor misprints corrected and a few references added