No Access Submitted: 02 August 1996 Accepted: 27 November 1996 Published Online: 31 August 1998
J. Chem. Phys. 106, 3545 (1997);
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  • Robert A. Morris
  • W. B. Knighton
  • A. A. Viggiano
  • Brian C. Hoffman
  • Henry F. Schaefer III
The gas-phase acidity (free energy of deprotonation, ΔGacid0) of H3PO4, orthophosphoric acid, was determined both experimentally and theoretically for the first time. Ion-molecule bracketing experiments yielded the result 1372 kJ mol−1Gacid0(H3PO4)>1331 kJ mol−1. The most reliable theoretical result, ΔGacid0H(H3PO4)=1343 kJ mol−1, is in agreement with experiment and was obtained using Brueckner methods with large basis sets.
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  1. © 1997 American Institute of Physics.