Please do not adjust margins The electrostatic energy ΔVelstat corresponds to the electrostatic interactions between the unperturbed charge distributions of the fragments BX3 and LB, which is usually attractive. The Pauli repulsion ΔEPauli comprises the destabilizing interactions between occupied orbitals on either fragment (more precisely, between same-spin occupied spin-orbitals on either fragment) and arises from the antisymmetrization of the Hartree wavefunction due to the Pauli principle. The orbital interactions ΔEoi term accounts for charge transfer (donor-acceptor interaction between an occupied orbital of one fragment with an empty orbital of the other fragment) and polarization (empty/occupied orbital mixing on one fragment due to the presence of another fragment). Finally, the dispersion energy ΔEdisp is added using Grimme's empirical correction. The PyFrag2019 program was used to facilitate these analyses. 32