[Chimera-users] command lines to replace "joint models"

Dear Chimera developers, I'm so sorry to interrupt you. I have to run Chimera in Linux,but there is no command line of "joint modeles".I need to get 2 modified amino acids or peptides together and not creating crashes.In windows,"joint models" is my best choice,it's very convient and perfect.But in Linux,I tried some command line,such as "combine","bond",but it can't automatically repositioning the models and the structure was not right. So,could you please tell me how to use command lines to replace "joint models" function? Thanks in advance Best Regards Daojiong Wang