An electron spin resonance study of Mn2+ doped calcium hydrazine carboxylate monohydrate

Abstract

Single crystals of calcium hydrazine carboxylate, monohydrate have been studied by ESR of Mn2+ doped in the calcium sites. X-band ESR indicated a large crystal field splitting necessitating experiments at Q band. The analysis shows two magnetically inequivalent (but chemically equivalent) sites withg xx = 2.0042±0.0038,g yy=2.0076 ±0.0029,g zz=2.0314±0.001,A zz=0.0099±0.0002 cm−1,A xx=0.0092±0.0002 cm−1,A yy=0.0082±0.0002 cm−1,D=3/2D zz=0.0558±0.0006 cm−1, andE=1/2 (D yy−D yy)=0.0127±0.0002 cm−1.One of the principal components of the crystal field, (D zz), is found to be along the Ca ↔ Ca direction in the structure and a second one, (D xx), along the perpendicular to the plane of the triangle formed by three neighbouring calciums. TheA tensor is found to have an orientation different from that of theg andD tensors reflecting the low symmetry of the Ca2+ sites.