R-dependent magnetic and structural properties in RMn2O5 with R = Y, Er, Ho, Dy, and Tb

We have synthesized a series of orthorhombic RMn2O5 with R=Y,Er,Ho,Dy, and Tb, and employed the techniques of x-ray powder diffraction and dc magnetic susceptibility in order to systematically study their R-dependent structural and magnetic properties. It is found that in spite of the similarity in the crystalline structures of these five samples, only YMn2O5 and ErMn2O5 show canted antiferromagnetic transitions at 45 K. Particularly for YMn2O5, the magnetization saturates at relatively low field (similar to 5 kOe) compared with that of the others (>20 kOe), suggesting that the magnetic moments of R-ions contribute significantly to the net moment of the system. (C) 2006 American Institute of Physics.