AMBER Archive (2003)

Subject: Re: noninteger charge

From: David A. Case (case_at_scripps.edu)
Date: Wed Feb 05 2003 - 12:59:32 CST

On Wed, Feb 05, 2003, eric hu wrote:

> Hi, when I add the QM calculated charges to the
> substrate, xleap tells me that the unperturbed charge
> is nonzero. I found that amber only takes four digits
> after the zero point instead of all six of them. In my
> case this error is 50%--xleap saids the total charge
> is 0.53. Will this be a big potential error in the
> simulation?
>

We would need an example: how can truncating the charge to four places
past the decimal point lead to a summed error of 0.53? I must not be
understanding what you are writing.

Also, when you say "amber only takes four digits..." what part of amber
are you referring to?

It really helps to be as explicit as you can when reporting problems to
the mailing list.

.regards...dac 

-- 

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David A. Case                     |  e-mail:      case_at_scripps.edu
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