Abstract
This is the data and associated new software required to run multi-state density-functional theory (MSDDFT) calculations by the GAMESS programme. Also, data and software needed to drive GAMESS based on output from the Gaussian-16 package is included. Sample input and output files are included, as well as Perl scripts and Fortran source code. A separate execution of the scripts is required to create the input specifications for each state to be included in the MSDFT, then after GAMESS is run more software is included to calculate the final state energies. The associated basic theory and results are described in "Multistate density functional theory applied with 3 unpaired electrons in 3 orbitals: the singdoublet and tripdoublet states of the ethylene cation" [1].