Electronic and magnetic structure of CsV2O5

We have studied the electronic structure of the spin-gapped system CsV 2 O 5 by means of an ab initio calculation. Our analysis and a reexamination of the susceptibility data indicate that the behavior of this system is much closer to that of an alternating spin-½ antiferromagnetic chain with significant inter-dimer coupling and weaker interchain couplings than that of isolated dimers as was initially proposed. Comparison to the vanadate family members α'-NaV 2 O 5 , γ-LiV 2 O 5 , and isostructural compounds like (VO) 2 P 2 O 7 is discussed.