Select structures are investigated further at the M06-2X /6-31G(d) level of theory(using Gaussian09). This level of theory was chosen as a good compromise between computational efficiency and accuracy as judged by comparison to DLPNO-CCSD(T) and CCSD(T)-F12a calculations . DFT is used in one of three ways. The first quick approach estimates DFT energies by reoptimizing the structure with the lowest SQM energy for DHA, VHF, and the TS and the electronic energy is used to compute the storage density and barrier. A benchmark investigation has been carried out by . The second approach is a more thorough DFT searches, used to obtain the final DFT energies. In the second approach a systematic conformer search is performed using SQM where each rotateable bond is rotated by ±120 • starting from the lowest energy structure found using the RDKit conformer generating algorithm. Each structure is energyminimized and in the case of the TSs the reacting bond is constrained. The minimized TS structure is then used as an initial guess for an unconstrained TS search. All unique conformers (conformers with Torsion Fingerprint Deviation that are less than 0.001 are considered identical) are then reoptimized with M06-2X/6-31G(d) and the structures with the lowest free energy are used to compute the storage density and barrier.