To couple spin relaxation times and molecular dynamics, we used Redfield equations 61 which connect T 1 , T 2 and hetNOE spin relaxation times to the Fourier transformation (Spectral density) of the second-order rotational correlation functions of N-H, C-H or C-D bonds. We calculated the rotational correlation functions, C(t), for peptide backbone N-H bonds and C-H bonds in SDS molecules using the equation implemented in the gromacs package