[gmx-users] g_chi

[Marieke van den Bosch]

Dear gromacs developers and users, 

a problem occured when looking at the flexibility
of my system using g_chi. phi and psi angles of
certain aminoacids are perfectly stable, the angle
vs time plot shows no changes. The output file
chi.log however gives values for the number of
transitions per ns in the order of 20 upto 97! The
order parameters look fine, see below.

Residue ILE7
 Angle [   AI,   AJ,   AK,   AL]  #tr/ns  S^2D  
--------------------------------------------
   Phi [   52,   51,   53,   58]   38.91    0.91
   Psi [   51,   53,   58,   59]    6.25    0.93
 Omega [   50,   49,   51,   53]    0.62    0.94
   Chi1[   51,   53,   54,   55]    0.00    0.98
   Chi2[   53,   54,   55,   57]   65.31    0.71


How is a dihedral transition defined?


Best regards, 

Marieke van den Bosch.

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