NMR characterization of spin-1/2 alternating antiferromagnetic chains in the high-pressure phase of (VO)2P2O7

摘要

Local-susceptibility measurements via the NMR shifts of $^{31}$P and $^{51}$Vnuclei in the high-pressure phase of (VO)$_{2}$P$_{2}$O$_{7}$ confirmed theexistence of a unique alternating antiferromagnetic chain with a zero-fieldspin gap of 34 K. The $^{31}$P nuclear spin-lattice relaxation rate scales withthe uniform spin susceptibility below about 15 K which shows that thetemperature dependence of both the static and dynamical spin susceptibilitiesbecomes identical at temperatures not far below the spin-gap energy.