Define net charge on molecule while using QEq

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1

You shouldn’t use the following:

fix qeq1 Ni qeq/dynamic 1 10 1.0e-3 200 param.qeq1

fix qeq2 MOF qeq/dynamic 1 10 1.0e-3 200 param.qeq1

fix qeq3 water qeq/dynamic 1 10 1.0e-3 200 param.qeq1

You should use this:

fix qeq1 all qeq/dynamic 1 10 1.0e-3 200 param.qeq1

With QEq, you don’t assign charges to atoms but the QEq algorithm does, so you don’t need to worry about “but I don’t know how to assign charge for it.” The only freedom you have with fix qeq/dynamic is the system charge, which you have set to +2 by assigning +2 to 1 Ni atom, but this +2 is redistributed to the entire system and does not stay on the Ni atom.

2

You shouldn’t use the following:

fix qeq1 Ni qeq/dynamic 1 10 1.0e-3 200 param.qeq1

fix qeq2 MOF qeq/dynamic 1 10 1.0e-3 200 param.qeq1

fix qeq3 water qeq/dynamic 1 10 1.0e-3 200 param.qeq1

You should use this:

fix qeq1 all qeq/dynamic 1 10 1.0e-3 200 param.qeq1

With QEq, you don’t assign charges to atoms but the QEq algorithm does, so you don’t need to worry about “but I don’t know how to assign charge for it.” The only freedom you have with fix qeq/dynamic is the system charge, which you have set to +2 by assigning +2 to 1 Ni atom, but this +2 is redistributed to the entire system and does not stay on the Ni atom.