[gmx-users] No default Angle types

[Justin A. Lemkul]

darrellk at ece.ubc.ca wrote:
> Dear All,
> I ran grompp and was presented with the following error:
> ERROR 0 [file "graphene_nm_test.top", line 51217]:
>   No default Angle types
> 
> Line 51217 of the topology file is:
>  5116 5115 5117 1
> 
> and atoms 5115 to 5117 are defined in the topology file as:
>   5115 opls_145 1 Grph C 4859 -0.12 12.011 ;
> qtot -0.12
>   5116 opls_146 1 Grph H 4859 0.06 1.008 ;
> qtot -0.06
>   5117 opls_146 1 Grph H 4859 0.06 1.008 ;
> qtot 0
> 
> My assumption is that this error means that there does not exist an
> angletype for this threesome of atoms in the ffolpsaabon.itp file.
> 

You are correct.  Take a closer look at the atom types:

opls_145   12.01100  ; Benzene C - 12 site JACS,112,4768-90. Use #145B for biphenyl

opls_146    1.00800  ; Benzene H - 12 site.

Both atom types correspond to benzene/aromatic sites.  So, in these aromatic 
species, there is no such thing as a ring CH2.

Maybe you want something more like:

opls_136   12.01100  ; alkane CH2

opls_140    1.00800  ; alkane H.

-Justin

> I looked within the ffoplsaabon.itp file for an entry of the form:
> HA CA HA
> 
> and, as expected, "pattern not found" was returned as the response.
> 
> So, I copied over the ffoplsaabon.itp file to my home (working) directory
> and added the following test entry:
>   HA     CA     HA      1   107.000    276.000   ; TEST PARAMETERS *****
> NOT VALID *** ONLY FOR TESTING
> 
> I expected that the ERROR O message above would disappear. But the error
> was still present. Could you please tell me what I need to do in order
> to resolve this error?
> 
> Much thanks in advance.
> 
> Darrell
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-- 
========================================

Justin A. Lemkul
Ph.D. Candidate
ICTAS Doctoral Scholar
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

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