Interaction energies associated with short intermolecular contacts of C--H bonds. Ab initio computational study of the C--Hter dot ter dot ter dot O contact interaction in CH sub 4 ter dot ter dot ter dot OH sub 2

Journal Article · Tue Oct 01 00:00:00 EDT 1991 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.461686· OSTI ID:5169801

Novoa, J J; Tarron, B ^[1]; Whangbo, M ^[2]; Williams, J M ^[3]

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1. Departamento de Quimica Fisica, Facultad de Quimica, Universidad de Barcelona, 08028-Barcelona (Spain)
2. Department of Chemistry, North Carolina State University, Raleigh, North Carolina (USA)
3. Chemistry and Materials Science Divisions, Argonne National Laboratory, Argonne, Illinois (USA)

To accurately evaluate the C--H{center dot}{center dot}{center dot}O contact interaction energy, {ital ab} {ital initio} calculations were performed on CH{sub 4}{center dot}{center dot}{center dot}OH{sub 2} at the self-consistent-field molecular orbital (SCF-MO) and MP2 levels with various quality basis sets including a near Hartree--Fock limit (HFL) one. The interaction energies calculated with truncated basis sets have small basis set superposition errors and become close to the near HFL results only when they include diffuse functions. This is attributed to the necessity of properly representing the lone pair electrons of oxygen that make short contact interaction with the C--H bond. Our MP2 calculations suggest that the conformation of CH{sub 4}{center dot}{center dot}{center dot}OH{sub 2} with one C--H{center dot}{center dot}{center dot}O contact is the only minimum-energy structure. At the MP2 level with the near HFL basis set, the binding energy of CH{sub 4}{center dot}{center dot}{center dot}OH{sub 2} is calculated to be 0.59{plus minus}0.05 kcal/mol. The potential energy curves of CH{sub 4}{center dot}{center dot}{center dot}OH{sub 2} calculated as functions of the H{center dot}{center dot}{center dot}O contact angles are consistent with the observation that the most frequently found H{center dot}{center dot}{center dot}O contact angles of organic solids are in the range {vert bar}{phi}{vert bar}{le}{similar to}60{degree} and {vert bar}{theta}{vert bar}{le}{similar to}30{degree}.

• DOE Contract Number: FG05-86ER45259; W-31109-ENG-38
• OSTI ID: 5169801
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 95:7; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKANES
CHEMICAL BONDS
CRYSTALS
HYDROCARBONS
HYDROGEN COMPOUNDS
INTERMOLECULAR FORCES
METHANE
MOLECULAR CRYSTALS
MOLECULAR ORBITAL METHOD
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
SELF-CONSISTENT FIELD
SOLIDS
WATER