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Methods and Applications in Ab Initio Thermochemistry

Karl K. Irikura           Research Opportunity Number 50.63.21.B4792

For predicting thermochemistry of small main-group molecules, quantum chemistry is sufficiently reliable that it can be used to settle experimental disagreements and to provide critical data that are not available experimentally. However, important challenges remain, such as transition-metal compounds and floppy or tautomerizing molecules. Determining the quantitative uncertainties associated with high-level predictions is also difficult; currently available wavefunction diagnostics are not yet reliable for this purpose and partition functions include uncontrolled approximations.