2013/03/07 by Jan H. Jensen, Jensen, Jan H., Jimmy Kromann +1
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #Chemical Physics (physics.chem-ph) #Chemical Thermodynamics and Molecular Structure #FOS: Physical sciences #Various Chemistry Research Topics
paper · pdf · doi:10.48550/arxiv.1303.1679
openalex publication_date 2013/03/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A new web-server called The Molecule Calculator (MolCalc) is presented. The entry page is a molecular editor (JSmol) for interactive molecule building. The resulting structure can then be used to estimate molecular properties such as heats of formation and other thermodynamic properties, vibrational frequencies and vibrational modes, and molecular orbitals and orbital energies. These properties are computed using the GAMESS program at either the RHF/STO-3G (orbitals and orbital energies) or PM3 level of theory (all other properties) in a matter of seconds or minutes depending on the size of the molecule. The results, though approximate, can help students develop a "chemical intuition" about how molecular structure affects molecular properties, without performing the underlying calculations by hand, a near impossible task for all but the simplest chemical systems.