Electronic paramagnetic resonance or rare-earth ions Yb3+, Pr3+, Dy3+, and Nd3+ in double molybdates and tungstenates

• Published in: Low temperature physics (Woodbury, N.Y.) N.Y.), 2010-07, Vol.36 (7), p.611-617
• Main Authors: Kobets, M. I., Khats’ko, E. N., Dergachev, K. G., Kalinin, P. S.
• Format: Article
• Language: English
• ISSN: 1063-777X; 1090-6517
• DOI: 10.1063/1.3482018

The particulars of the EPR spectrum of magnetically concentrated crystals of double molybdates and tungstenates with a crystal structure of low symmetry were studied at liquid-helium temperatures in the frequency range 15–120GHz. The directions of the principal magnetic axes were determined and the principal values of the g tensors were obtained for all experimental crystals KYb(MoO4)2, CsPr(MoO4)2, RbDy(MoO4)2, and RbNd(WO4)2. Two non-equivalent geometric centers were found in KYb(MoO4)2 and RbDy(MoO4)2 crystals; the local axes of the centers were turned in different directions relative to the crystallographic axes a and c by 34° and 25°. The dipole-dipole interaction energy was estimated as Edd∼0.1cm−1 for KYb(MoO4)2. It was shown that the lowest states of CsPr(MoO4)2 are close-lying singlets (quasidoublet) with splitting Δ∼0.2cm−1.