ORCA — расчёт колебательных частот и термохимии

★ 7.5 · general

orca-freq is a Claude Code skill that runs vibrational frequency calculations in ORCA, computing IR intensities, zero-point energy (ZPE), and thermochemical quantities — enthalpy, entropy, and Gibbs free energy — at a specified temperature and pressure. The input structure must be optimized at the same level of theory used for the frequency job; otherwise spurious imaginary frequencies appear. The skill supports both a standalone freq node and an opt→freq chain connected via the graph-based catgo_workflow tool, submitted to the Expanse HPC cluster; an optional gibbs_energy node recalculates thermodynamics at non-standard conditions. It is used in computational chemistry workflows for obtaining IR spectra, confirming energy minima (no imaginary frequencies), or verifying transition states (exactly one imaginary frequency).