Where Ŝ1 and Ŝ2 are the spin operators for the spins at sites 1 and 2 respectively and 2J is the magnetic exchange coupling constant. A positive (negative) sign of 2J indicates ferromagnetic (antiferromagnetic) coupling. The broken symmetry formalism provides an efficient method to determine the magnetic exchange coupling constant within the single determinant framework of DFT. To determine the value of 2J, we have employed Yamaguchi's formula since it gives accurate values in both low and high overlap regimes of the magnetic orbitals. It is expressed as, 40