“…Theoretically, some quantum state referred to in the later part of this paper e.g quasi-equilibrium state does not evolve under Hamiltonian system except they are reduced with the eigenbasis blocks of the spin environment Hamiltonian (Walls & Lin, 2006). This problem was solved in this paper by estimatingdifferently for the reduction of the eigenbasis blocks of the spin environment Hamiltonian-using the Bloch NMR equation to solve the Schrödinger equations (Emetere, 2013b(Emetere, , 2014c and then inserting the solutions (which are the reduced eigenbasis) into a spin environment Hamiltonian in order to analyze the mechanism of femtosecond spin dynamics. Recall that validity of the NMR relaxation rates to analyze the femtosecond spin dynamics had been confirmed in the experimental investigation on the molecular rotation and intermolecular motions from picosecond to nanosecond time scale (Ishima & Torchia, 2000;Palmer III, 2001).…”