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Alex Granovsky
gran@classic.chem.msu.su

The problem is that the structure is very compact and inter-atomic
distances are all short so Firefly generated a wast amount of primitive
internal coordinates esp. torsions. This huge number of primitives
would require lots of memory and may actually slows down calculations.


To avoid this problem one would need to redefine atomic van-der-Waals
radii used in construction of internals. Unfortunately it is
impossible to do this with present Firefly versions.

Kind regards,
Alex Granovsky


On Tue Jul 16 '13 8:42am, Siddheshwar Chopra wrote
--------------------------------------------------
>Dear Sir,
>Arshad Sir unfortunately your suggestion didn't work. Prof. Alex thanks for the suggestion. Now the program runs with cartesian coords. very well. But I want to use the internal coordinates. What is the workaround to this problem? I am using "C1" no symmetry and cartesian coordinates, which will increase the computation time. Does it mean I should increase the RAM (it is currently 2GB). I even increased the virtual memory, but of no help. What should I do? I do not want to compromise on internal coordinates. The structure seems to possess no symmetry as per Gabedit.

>Regards,

>On Mon Jul 15 '13 3:30pm, Alex Granovsky wrote
>----------------------------------------------
>>Dear Siddheshwar,

>>the code generates too much primitive coordinates.
>>It seems you need to disable DLCs. In addition, check
>>your input geometry for errors.

>>Kind regards,
>>Alex Granovsky
>>
>>
>>On Mon Jul 15 '13 2:56pm, Arshad Mehmood wrote
>>----------------------------------------------
>>>On Mon Jul 15 '13 1:32pm, Siddheshwar Chopra wrote
>>>--------------------------------------------------
>>>>Dear Sir,
>>>>Please find the sample o/p file attached. I am getting this error repeatedly. The problem is that the error shows different memory requirements everytime. My computer has two cores. I even tried reducing number of cores to one, but problem persists. Please help.

>>>>Regards,

>>>>

>>>Dear Siddheshwar,
>>>Just Replace MEMORY=53113807 with MEMORY=20 or even with more smaller. I hope you will find the result. For further info. Check this thread:

>>>http://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C34df668afbHW-7091-955+00.htm

>>>Regards,

>>>Arshad Mehmood