Author Topic: Is it possible to increase the maximum number of atoms and basis functions?  (Read 6654 times)

evgeniy

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Dear Developers of Turbomole,

I am wondering whether it is possible to make the
large version of Turbomole even larger, namely to
increase the maximum number of atoms and basis
functions, say in 2 times (currently the large version
supports maximum 1400 atoms and 2100 basis functions,
if I am not mistaken). I, and I guess many other users,
will very appreciate further enhancing the capabilities
of Turbomole  ;).

Best wishes,
Evgeniy

christof.haettig

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Hey,

yes,  1400 atoms and 21 000 basis function is the limit in the binaries for huge cases.
These limitations will of cause in the future be extended and/or eliminated. But presently the code still contains a few places where arrays depending on the square of these parameters and combinations of them appear, meaning that simple increasing the limits in TM's parameter file increases the memory demands for all calculations (even if you don't have such large cases).
But if you need this, you might ask COSMOLogic for a special version...

Christof

uwe

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Re: Is it possible to increase the maximum number of atoms and basis functions?
« Reply #2 on: September 15, 2021, 04:42:41 PM »
Hi there,

as old posts are often found and not being recognized as outdated, here's an update:

Turbomole does not have a limit for the number of atoms or basis functions any more.
However, the size of the input is limited by your hardware, especially the amount of memory that is available.

Some modules like dscf do hardly need any memory, others like 2nd derivatives (aoforce,...) have higher requirements.