Superposition-model analysis of zero-field splitting parameters for Mn2+ in NSHH and MSHH single crystals

• DOI: 10.1007/s12648-013-0251-2
• Publication Date: 2013-02-19T07:51:55Z
• Authors: R. S. Bansal; M. Bharti; S. S. Hooda
• Keywords: 0103 physical sciences; 01 natural sciences

The superposition-model suggested by Newman has been used to calculate the zero-field splitting parameters (ZFS) at room temperature that fit the experimental data taken from the literature. The satisfactory reproduction of experimental values of ZFS parameters indicates that Mn2+ substitute in place of Ni2+ and Mg2+ in the lattices and does not cause appreciable local distortion in the host crystals NSHH and MSHH. The calculations are made with the assumption that the total field experienced at an ion in a crystal is due to nearest neighbor ions, using power law exponent t2 = 7 ± 1 and t4 = 10 ± 1 the reference distance Rο = 0.22 nm for Mn2+ surrounded by oxygens. The superposition model analysis shows that for large values of ZFS parameters b20, b22, b40, b42 and b44, intrinsic parameters \( \bar{b}_{ 2} \) and \( \bar{b}_{ 4} \) can be estimated with suitable errors but for small values of these spin–Hamiltonian parameters it is very difficult to predict the correct sign and magnitude.