[gmx-users] Error energy minimization: No such moleculetype NA

[Gonzalez Fernandez, Cristina]

Dear Gromacs users,



I am trying to perform the energy minimization after adding sodium ions. When I do the grompp to generate the .tpr file that will be used for the energy minimization, I get this error:



Fatal error:

No such moleculetype NA



I have checked the .top file and its true that there is not NA in moleculetype, but I have simulated other molecules with ions and I have never define any moleculetype with the ions.



I have introduced a moleculetype with NA, but then I get this error:



Moleculetype "NA" contain contains no atoms



How can I solve it? What are the atoms, exclusions, constraints... I have to define?





Could anyone help me?

Any help would be appreciated.

Best,

C.