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Title: Size-extensivity-corrected multireference configuration interaction schemes to accurately predict bond dissociation energies of oxygenated hydrocarbons

Oxygenated hydrocarbons play important roles in combustion science as renewable fuels and additives, but many details about their combustion chemistry remain poorly understood. Although many methods exist for computing accurate electronic energies of molecules at equilibrium geometries, a consistent description of entire combustion reaction potential energy surfaces (PESs) requires multireference correlated wavefunction theories. Here we use bond dissociation energies (BDEs) as a foundational metric to benchmark methods based on multireference configuration interaction (MRCI) for several classes of oxygenated compounds (alcohols, aldehydes, carboxylic acids, and methyl esters). We compare results from multireference singles and doubles configuration interaction to those utilizing a posteriori and a priori size-extensivity corrections, benchmarked against experiment and coupled cluster theory. We demonstrate that size-extensivity corrections are necessary for chemically accurate BDE predictions even in relatively small molecules and furnish examples of unphysical BDE predictions resulting from using too-small orbital active spaces. We also outline the specific challenges in using MRCI methods for carbonyl-containing compounds. The resulting complete basis set extrapolated, size-extensivity-corrected MRCI scheme produces BDEs generally accurate to within 1 kcal/mol, laying the foundation for this scheme's use on larger molecules and for more complex regions of combustion PESs.
Authors:
 [1] ;  [2] ; ;  [3] ;  [4] ;  [3] ;  [5] ;  [5]
  1. Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544 (United States)
  2. Department of Chemistry, Princeton University, Princeton, New Jersey 08544 (United States)
  3. Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States)
  4. Department of Chemical Sciences, University of Napoli Federico II, Napoli 80120 (Italy)
  5. (United States)
Publication Date:
OSTI Identifier:
22255201
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ALCOHOLS; ALDEHYDES; CARBOXYLIC ACIDS; COMBUSTION; CONFIGURATION INTERACTION; DISSOCIATION ENERGY; FOUNDATIONS; HYDROCARBONS; MOLECULES; POTENTIAL ENERGY; SURFACES