High-accuracy thermodynamic calculations for lignocellulosic biomass molecules using re-optimized composite methods

Abstract We developed a highly efficient composite quantum chemical method tailored for biomass-derived molecules. The method achieves chemical accuracy in evaluating CCSD(T)/CBS correlation energies and enthalpies of formation while reducing computational costs by over 2 orders of magnitude. This efficiency makes large-scale thermodynamic analysis feasible. Furthermore, the approach can be extended to condensed-phase and catalytic systems, enabling quantitative insights into biomass conversion and related chemical processes in diverse environments.