[gmx-users] g_angle between three atoms

[Cyrus Djahedi]

Hi all. I'm interested in calculating a specific angle between three atoms situated in adjacent cellulose polymer chains. So I made the following index groups:
Group     8 (a_3194_a_2348_a_4463) has     3 elements
Group     9 (a_4463_a_3194_a_2348) has     3 elements
Group    10 (a_2348_a_4463_a_3194) has     3 elements

Notice how its the same atoms arranged in different order, yet GROMACS calculates the same angle over and over, the one Im NOT interested in. Any tips?
/ Cyrus