The calculation of the effective interaction parameter in LDA+U method by linear response approach for Fe(OH)2

In this paper we have investigated the electronic properties of Fe(OH)2 hydroxide by using the LSDA+U as well as the generalized gradient approximation. Our calculations for the iron-hydroxide show that the LSDA results are greatly at variance with experimental findings. On the other hand we have shown that LSDA+U is capable of opening a gap at the Fermi level resulting in insulating ground state in agreement with experimental observations.