I am runnig a QMMM optimization of a system containing protein and carbohydrate parts. In the optimization step the qm-region is treated with TURBOMOLE and the mm-region is treated with DL-POLY using the CHARMM topology and parameter files (par_all36_prot.prm and par_all36_carb.prm). I can't use two parameter files as the ' charmm_parameter_file' argument where I have to use both the parameter files in a single argument . I have tried to 'list' the parameter files and the error was showing as 'unmatched open quote in list' . Kindly help me to solve the issue or let me know if there is any other way to provide the parameter files in a single argument.