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I am trying to make benzene molecules using the OPLS 1990 JACS paper, which is simply LJ+Coulomb and has no bonds, angles, or torsion.
If I do the following, I get "Error in CBMC growing scheme.. No atoms can be grown, check the connectivity of your molecule." How do I solve this error?
I also changed the end of the force_field_mixing_rules file from "Lorentz-Berthelot" to "Jorgensen"
I would like to avoid implementing bonds and angles in the topology if possible because I believe the calculations will be faster.

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# critical constants: Temperature [T], Pressure [Pa], and Acentric factor [-]
562.05
4894000.0
0.2092
# Number Of Atoms
12
# Number of groups
1
# benzene-group
rigid
# number of atoms
12
# atomic positions
0 C_benz  0.00000000    0.00000000    0.00000000
1 C_benz  1.39200000    0.00000000    0.00000000
2 C_benz  2.08800000    1.20550736    0.00000000
3 C_benz  1.39200051    2.41101443   -0.00119599
4 C_benz  0.00000000    2.41101459   -0.00167420
5 C_benz -0.69600000    1.20550717   -0.00068061
6 H_benz -0.54000000   -0.93530733    0.00044182
7 H_benz  1.93200000   -0.93530654    0.00129125
8 H_benz  3.16799982    1.20550747    0.00062273
9 H_benz  1.93200056    3.34632183   -0.00125416
10 H_benz -0.53999901    3.34632180   -0.00260212
11 H_benz -1.77600000    1.20550708   -0.00085731
# Chiral centers Bond  BondDipoles Bend  UrayBradley InvBend  Torsion Imp. Torsion Bond/Bond Stretch/Bend Bend/Bend Bend/Torsion IntraVDW IntraCoulomb
               0   0            0    0            0       0        0            0         0            0         0            0        0            0

Hi.

I am interested in getting pure component vapor pressures and am thinking of using GEMC. I have read the manual about CO2 and checked the Non-Basic/Gibbs_CO2 example and have a few questions.

1. What output property should I use to determine if I am using enough cycles and molecules?

2. The adsorbate/adsorbate energy shows a lot of variance. How much fluctuation is generally acceptable to ensure the simulation is in equilibrium?

3. What is a good rule of thumb in changing input parameters to get stable results?
(ex.  increase no. of cycles > increase molecules > increase swaps)

Thanks in advance!