 The  free energy change in conformation transition of S protein is introduced and we demonstrated that it includes two parts, one from the difference of conformation potential and another from the variation of structural elasticity.
<coherence>  The  free energy change in conformation transition of S protein is introduced and we demonstrated that it includes two parts, one from the difference of conformation potential and another from the variation of structural elasticity.
 The free energy change in conformation transition of S protein . We demonstrated that the free energy includes two parts, one from the difference of conformation potential and another from the variation of structural elasticity.