Original filenames:
MOLEC8-B040-OPT-FREQ2.gout
MOLEC1-B001-OPT-FREQ2.gout
MOLEC2-B010-OPT-FREQ2.gout
MOLEC10-B002-OPT-FREQ2.gout
Sorted filenames:
MOLEC8-B040-OPT-FREQ2.gout
MOLEC2-B010-OPT-FREQ2.gout
MOLEC10-B002-OPT-FREQ2.gout
MOLEC1-B001-OPT-FREQ2.gout