Zero field splitting parameters of Mn2+ in Bis (l-asparaginato) Zn (II) at interstitial orthorhombic symmetry site

► Superposition model is used to find the crystal field parameters of Mn2+ in [Zn (l-asn)2]. ► Zero field splitting parameters are then determined with the microscopic spin Hamiltonian theory. ► Parameters evaluated theoretically are in good agreement with the experimental values. ► The results suggest that the Mn2+ ion occupies interstitial site in [Zn (l-asn)2]. ► This is consistent with the experimental observation and conclusion.