Author Topic: Use of $m-matrix directive to fix certain cartesians during optimization  (Read 4219 times)


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Dear Developers and Users of Turbomole,

I am interested in a partial optimization in cratesians
with fixing cartesians of certain atoms. In one of the posts
I found that one can do this directly in the coord file like:

0.0 0.0 0.0    h 1 1 0

(to fix z-component of the h atom in this case).
This way however didn't work out for me - during the
optimzation the atoms with the "1 1 0" mask change
their coordinates. So, I guess the right way to achieve
the aim is to use $m-matrix directive as described in the
manual. But I didn't get quite what the example in the
manual means. It looks like:

1   0.0 0.0 0.0
10 1.0 0.0 0.0
11 1.0 1.0 0.0

Does it mean that atom 1 will be completely
fixed, atom 10 will be fixed in the yz-plane and
only z-component will be fixed for atom 11?

Many thanks!