Title: Diagnostics of Data-Driven Models: Uncertainty Quantification of PM7 Semi-Empirical Quantum Chemical Method

Abstract

Abstract We report an evaluation of a semi-empirical quantum chemical method PM7 from the perspective of uncertainty quantification. Specifically, we apply Bound-to-Bound Data Collaboration, an uncertainty quantification framework, to characterize (a) variability of PM7 model parameter values consistent with the uncertainty in the training data and (b) uncertainty propagation from the training data to the model predictions. Experimental heats of formation of a homologous series of linear alkanes are used as the property of interest. The training data are chemically accurate , i.e., they have very low uncertainty by the standards of computational chemistry. The analysis does not find evidence of PM7 consistency with the entire data set considered as no single set of parameter values is found that captures the experimental uncertainties of all training data. A set of parameter values for PM7 was able to capture the training data within ±1 kcal/mol, but not to the smaller level of uncertainty in the reported data. Nevertheless, PM7 was found to be consistent for subsets of the training data. In such cases, uncertainty propagation from the chemically accurate training data to the predicted values preserves error within bounds of chemical accuracy if predictions are made for the molecules of comparable size.more » Otherwise, the error grows linearly with the relative size of the molecules.« less

Authors:

Oreluk, James; Liu, Zhenyuan; Hegde, Arun; Li, Wenyu; Packard, Andrew; Frenklach, Michael; Zubarev, Dmitry

Publication Date:

Wed Sep 05 00:00:00 EDT 2018

Research Org.:

Univ. of Utah, Salt Lake City, UT (United States)

Sponsoring Org.:

USDOE

OSTI Identifier:

1467754

Alternate Identifier(s):

OSTI ID: 1545322

Grant/Contract Number:  

NA0002375

Resource Type:

Published Article

Journal Name:

Scientific Reports

Additional Journal Information:

Journal Name: Scientific Reports Journal Volume: 8 Journal Issue: 1; Journal ID: ISSN 2045-2322

Publisher:

Nature Publishing Group

Country of Publication:

United Kingdom

Language:

English

Subject:

42 ENGINEERING