Uncertainty quantification in thermochemistry, benchmarking electronic structure computations, and Active Thermochemical Tables

The accepted convention for expressing uncertainties of thermochemical quantities, followed by virtually all thermochemical tabulations, is to provide earnest estimates of 95% confidence intervals. Theoretical studies frequently ignore this convention, and, instead, provide the mean absolute deviation, which underestimates the recommended thermochemical uncertainty by a factor of 2.5–3.5 or even more, and thus may vitiate claims that “chemical accuracy” (ability to predict thermochemical quantities within ±1 kcal/mol) has been achieved. Furthermore, copropagating underestimated uncertainties for theoretical values with uncertainties found in thermochemical compilations produces invalid uncertainties for reaction enthalpies. Two groups of procedures for determining the accuracy of computed thermochemical quantities are outlined: one relying on estimates that are based on experience, the other on benchmarking. Benchmarking procedures require a source of thermochemical data that is as accurate and reliable as possible. The role of Active Thermochemical Tables in benchmarking state-of-the-art electronic structure methods is discussed. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. International Journal of Quantum Chemistry published by Wiley Periodicals, Inc.

[1]  B. Ruscic,et al.  Improved accuracy benchmarks of small molecules using correlation consistent basis sets , 2013, Theoretical Chemistry Accounts.

[2]  J. Aguilera-Iparraguirre,et al.  Accurate ab initio computation of thermochemical data for C3Hx (x=0,…,4) species , 2008 .

[3]  B. Ruscic,et al.  W4 theory for computational thermochemistry: In pursuit of confident sub-kJ/mol predictions. , 2006, The Journal of chemical physics.

[4]  Raghu N. Kacker,et al.  Uncertainty associated with virtual measurements from computational quantum chemistry models , 2004 .

[5]  B. Ruscic,et al.  Pulsed field-ionization photoelectron-photoion coincidence study of the process N2+hnu-->N++N+e-: bond dissociation energies of N2 and N2+. , 2005, The Journal of chemical physics.

[6]  Jan M. L. Martin,et al.  TOWARDS STANDARD METHODS FOR BENCHMARK QUALITY AB INITIO THERMOCHEMISTRY :W1 AND W2 THEORY , 1999, physics/9904038.

[7]  Melita L. Morton,et al.  IUPAC Critical Evaluation of Thermochemical Properties of Selected Radicals. Part I , 2005 .

[8]  Branko Ruscic,et al.  High-accuracy extrapolated ab initio thermochemistry. III. Additional improvements and overview. , 2008, The Journal of chemical physics.

[9]  John A. Montgomery,et al.  A complete basis set model chemistry. V. Extensions to six or more heavy atoms , 1996 .

[10]  Mihaly Kallay,et al.  W3 theory: robust computational thermochemistry in the kJ/mol accuracy range. , 2003, Journal of Chemical Physics.

[11]  B. Ruscic Active thermochemical tables: water and water dimer. , 2013, The journal of physical chemistry. A.

[12]  Gregor von Laszewski,et al.  Active Thermochemical Tables: thermochemistry for the 21st century , 2005 .

[13]  F. Rossini The heat of formation of water , 1931 .

[14]  L. Curtiss,et al.  Gaussian-4 theory. , 2007, The Journal of chemical physics.

[15]  Branko Ruscic,et al.  Active Thermochemical Tables: dissociation energies of several homonuclear first-row diatomics and related thermochemical values , 2013, Theoretical Chemistry Accounts.

[16]  Juana Vázquez,et al.  HEAT: High accuracy extrapolated ab initio thermochemistry. , 2004, The Journal of chemical physics.

[17]  D. Tew,et al.  Atomization energies from coupled-cluster calculations augmented with explicitly-correlated perturbation theory , 2009 .

[18]  Barry N. Taylor,et al.  Guidelines for Evaluating and Expressing the Uncertainty of Nist Measurement Results , 2017 .

[19]  Branko Ruscic,et al.  Active Thermochemical Tables: accurate enthalpy of formation of hydroperoxyl radical, HO2. , 2006, The journal of physical chemistry. A.

[20]  Henry F. Schaefer,et al.  In pursuit of the ab initio limit for conformational energy prototypes , 1998 .

[21]  Kaizar Amin,et al.  Introduction to Active Thermochemical Tables: Several “Key” Enthalpies of Formation Revisited† , 2004 .

[22]  B. Ruscic,et al.  Heats of formation of C(6)H(5)(•), C(6)H(5)(+), and C(6)H(5)NO by threshold photoelectron photoion coincidence and active thermochemical tables analysis. , 2010, The journal of physical chemistry. A.

[23]  L. Curtiss,et al.  Gaussian-3 (G3) theory for molecules containing first and second-row atoms , 1998 .

[24]  Juana Vázquez,et al.  High-accuracy extrapolated ab initio thermochemistry. II. Minor improvements to the protocol and a vital simplification. , 2006, The Journal of chemical physics.