AMBER Archive (2003)

Subject: Re: ibelly and ntr

From: David A. Case (case_at_scripps.edu)
Date: Tue Apr 15 2003 - 18:13:11 CDT

On Tue, Apr 15, 2003, Youyi Peng wrote:

> I can't really understand the differnece between ibelly=1 and ntr=1,
> both for frozen /restrained atoms...

ibelly=1 are *con*straints: the frozen atoms cannot move at all.

ntr=1 are *re*straints: the restrained atoms can move, but won't move far;
      how far depends on the size of the force constant you use.

I'd recommend restraints to keep the backbone (nearly) fixed, but there is
no fundamental reason not to use constraints...

..good luck...dac 

-- 

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