Author Topic: Problem during setting up the Hückel matrix  (Read 2356 times)

valacar

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Problem during setting up the Hückel matrix
« on: February 13, 2015, 04:29:16 pm »
Hi everyone,

I am calculating just some small molecules in adduct formation and for some of them I encounter the following problem when setting up the Hückel matrix during the define step:

 ERROR: non-positive definite matrix in Cholesky decomposition (routine: usad)
    of overlap matrix in project.f

MODTRACE: no modules on stack

 negative root in usad, see output
 define ended abnormally

Has anyone of you an idea, what the problem could be?

Thanks.

uwe

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Re: Problem during setting up the Hückel matrix
« Reply #1 on: February 16, 2015, 02:29:57 pm »
Hello,

no idea. I'd recommend to send the input to the Turbomole support team (turbomole at cosmologic dot de).

Regards,

Uwe