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Dear Gayen,<BR>
<BR>
It stands for different atom types of the same element.<BR>
<BR>
For instance, in all atom OPLS parameter model for acetone, following atom types are being used.<BR>
CT, 0_2, C_2 and HC for methyl carbons, keto oxygen, carbonyl carbon and methyl hydrogens respectively. Indeed, CT( for methyl Carbon) and C_2 (for keto carbon) have to be specific, especially when bond angle, length and dihedral ( in the parameter file ) are mentioned.<BR>
<BR>
Hope this helps.<BR>
<BR>
On Mon, 23 Jun 2008 Mark Abraham wrote :<BR>
>ANINDITA GAYEN wrote:<BR>
>><BR>
>>--- On Mon, 23/6/08, ANINDITA GAYEN <aninditagayen@yahoo.co.in> wrote:<BR>
>><BR>
>>> From: ANINDITA GAYEN <aninditagayen@yahoo.co.in><BR>
>>>Subject: To: gmx-users@gromacs.org<BR>
>>>Date: Monday, 23 June, 2008, 11:47 AM<BR>
>>>Hello Al,<BR>
>>><BR>
>>><BR>
>>>Can someone tell me what is the meaning of CT, CT_2, C_3,<BR>
>>>C_2 etc atomtypes defined in the ffoplsaabon.itp? I have<BR>
>>>not found it in the manual.<BR>
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