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Search Publications by: Karl K. Irikura (Fed)

Displaying 76 - 100 of 107

Gas Phase Thermochemistry of Iron Oxides and Hydroxides: Portrait of a Super-Efficient Flame Suppressant

November 1, 1999

Author(s)

C B. Kellogg, Karl Irikura

In the search for non-ozone depleting Halon (CF 3Br) replacements, several metals, including iron, have been identified as super-efficient flame suppressants. Although some thermochemical data exist for the species that are thought to be most important in

Predicting Unexpected Chemical Reactions by Isopotential Searching

October 1, 1999

Author(s)

Karl K. Irikura, Russell D. Johnson III

The reactions of a chemical system are dictated by the corresponding potential energy surface (PES). Since reasonably accurate PESs are now available from quantum chemical calculations, a great deal of chemistry can, in principle, be predicted using

The Ionization Energy of CF 3 : When Does Entropy Matter in Gas-Phase Reactions?

September 1, 1999

Author(s)

Karl K. Irikura

A minor controversy has emerged recently over the value of the ionization energy of the trifluoromethyl radical, CF 3. Apparently solid evidence supports both high values, IE a {nearly equal to} 9.05 eV, and low values, IE a {nearly equal to} 8.65 eV

Inexpensive Vibrational Anharmonicities from Estimated Derivatives: Diatomic Molecules

December 1, 1998

Author(s)

P Hassanzadeh, Karl Irikura

Acetylacetonate (acac) Anion in the Gas Phase: Predicted Vibrational Spectra and Photodetachment Energies

September 1, 1998

Author(s)

Karl K. Irikura

The geometry and vibrational spectrum of the gas-phase acetylacetonate anion [acac-; (CH 3CO) 2CH -] are predicted using ab initio molecular orbital theory. At the MP2/6-31+G**//HF/6-31+G* level there are three stable conformers. In order of increasing

Systematic Errors in ab Initio Bond Dissociation Energies

August 1, 1998

Author(s)

Karl K. Irikura

Bond dissociation energies (D o) for 41 small molecules were calculated at 19 levels of ab initio theory up to CCSD(T)/cc-pVTZ, using geometries and vibrational zero-point energies from B3LYP/6-31G* hybrid density-functional calculations. Empirical

Experimental and ab initio Study of the Infrared Spectra of Ionic Species Derived From PF5, PF3, and F3PO and Trapped in Solid Neon

May 1, 1998

Author(s)

C Lugez, Marilyn E. Jacox, Karl K. Irikura

When a Ne:PF 5 or a Ne:PF 3 is codeposited a 5 K with a beam of neon atoms that have been excited in a microwave discharge, the infrared spectrum of the resulting solid shows a complicated pattern of new absorptions. Little fragmentation of PF 5 into PF 3