All Gaussian09 input files were prepared using QUBEKit, which takes PDB files and the corresponding BOSS/MCPRO style z-matrices generated using the LigParGen web server as input. All optimization routines and frequency calculations used for the bond stretching and angle bending terms were performed with the ωB97X-D 78 functional using the 6-311++G(d,p) basis set and a vibrational scaling factor of 0.957. Users of QUBEKit are free to choose their own QM methods based on required accuracy and computational expense. For comparison, Tables and show the derived bond and angle parameters of Nbutyl-1-butanamine computed using ωB97X-D/6-311++G(d,p) and MP2/6-311++G(d,p).