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Uncertainty Associated With Virtual Measurements From Computational Quantum Chemistry Models Using the Guide to the Expression of Uncertainty in Measurement
Published
Author(s)
Karl K. Irikura, Russell D. Johnson III, Raghu N. Kacker
Abstract
The output of a computer model for the value of a measurand is frequently referred to as a virtual measurement to distinguish it from a physical measurement determined from laboratory experiments. Any measurement, physical or virtual, is incomplete without a statement of its associated uncertainty. The science and technology of making high quality physical measurements and quantifying their uncertainties has matured over many decades. The science and technology of making virtual measurements is evolving. In this paper we propose an approach for quantifying the uncertainty associated with the predictions of the properties of molecules from computational quantum chemistry models. The proposed approach is based on the Guide to the Expression of Uncertainty in Measurement published by the International Standards Organization (ISO) and makes use of the Computational Chemistry Comparison and Benchmark Database (CCCBDB) maintained by the National Institute of Standards and Technology (NIST).
ab initio, computational chemistry, computational chemistry comparison and b, density functional theory, quantum chemistry, uncertainty in measurement, virtual measurement
Citation
Irikura, K.
, Johnson, R.
and Kacker, R.
(2004),
Uncertainty Associated With Virtual Measurements From Computational Quantum Chemistry Models Using the Guide to the Expression of Uncertainty in Measurement, Siam Journal on Scientific Computing, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=831888
(Accessed October 27, 2025)