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** Re^2: Geometry optimization with artifitial restrictions for part of molecule **
Pavel Semenyuk

psemenyuk@belozersky.msu.ru

On Mon Nov 15 '10 2:19am, sanya wrote

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>>I want to optimize geometry with artificial restriction - group of atoms is plane (but not constant, bond lenthes are variable), and no restrictions for the rest of molecule (2 dihedral angles equal to pi).

>>Really, I want to calculate a difference between energies of molecule in equilibrium geometry and restricted-optimal geometry. >The easiest way is to freeze cartesian coordinates, namely, z-coordinate, and optimize in cartesians. But you should first place your molecule properly. An alternative way is to place a dummy atom above the central atom of your planar group and set angles X-A-B 90 grad (X is dummy, A and B belong to the planar group). Try both ways.

Thank you! But the main question was about syntax and groups that i should edit. And I seem to solve it out now using firefly samples.

Thu Nov 18 '10 1:39pm

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