Size reduction-induced chain breaking in Haldane-chain compounds SrNi2−xMgxV2O8 (x  =  0 and 0.1)

The size reduction-induced chain breaking in the spin-1 Haldane-chain SrNi2-x Mg x V2O8 is reported by magnetization and electron spin resonance measurements, implying that a reduced sample grain size breaks the long chain and creates a considerable number of S’  =” 1/2 edge spins, resulting in the enhancement of Magnetization and the decrease ofHaldane gap in the samples.