To screen large numbers of compounds for qualitative exploration of linear carbonate functional space, we utilized accessible levels of theory that can perform optimization calculations on a reasonable time scale. Ab initio calculations with B3LYP orbitals are not tractable on a large scale, however we compute ab initio energies for three monomers to show the qualitative comparison between other levels of theory. To compare energetics in isolation, each of the states were optimized at the B3LYP level in gas phase after being optimized with DFTB for TS optimizations and geometry optimizations. The chosen representative conformers were then calculated with single point DFTB for the energetics discussed in the results section. Gaussian software was used for ab initio geometry relaxations and transition state optimizations with a convergence criteria of 10 -6 Hartree/bohr. Amsterdam modeling suite was used to carry out DFTB calculations, with PM7 and GFT1-N parametrizations, respectfully. Solvents were added to DFTB through a continuum model with 230 points to create the mesh for interactions, an implementation of the generalized born and surface area model. By utilizing this scheme with multiple levels of theory, we can explore a much wider materials space. DFTB calculations take less than one minute for an optimization, and optimizations with Gaussian can take several hours, even for our molecules which all have less than 40 atoms. We estimate an increase in speed of approximately 2 or 3 orders of magnitude.