Ariadne-88: An ab initio monoconfigurational closed and open shell direct electronic energy calculation using elementary Jacobi rotations

This article presents N2+ fragment yields following nitrogen K-shell photo-absorption in the NH+ molecular ion measured at the SOLEIL synchrotron radiation facility in the photon energy region 390–450 eV. The combination of the high sensitivity of the merged-beam, multi-analysis ion apparatus (MAIA) with the high spectral resolution of the PLEIADES beamline helped to resolve experimentally vibrational structures of highly excited [N1s−1H]*+ electronic states with closed or open-shell configurations. The assignment of the observed spectral features was achieved with the help of density functional theory (DFT) and post-Hartree Fock Multiconfiguration Self-Consistent-Field/Configuration Interaction (MCSCF/CI) ab-initio theoretical calculations of the N1s core-to-valence and core-to-Rydberg excitations, including vibrational dynamics. New resonances were identified compared to previous work, owing to detailed molecular modeling of the vibrational, spin-orbit coupling and metastable state effects on the spectra. The latter are evidenced by spectral contributions from the 4Σ− electronic state which lies 0.07 eV above the NH+2Π ground state.

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Spectroscopy of YO from first principles

Physical Chemistry Chemical Physics ◽

10.1039/c9cp03208h ◽

2019 ◽

Vol 21 (41) ◽

pp. 22794-22810 ◽

Cited By ~ 1

Author(s):

Alexander N. Smirnov ◽

Victor G. Solomonik ◽

Sergei N. Yurchenko ◽

Jonathan Tennyson

Keyword(s):

Ab Initio ◽

Yttrium Oxide ◽

Diatomic Molecule ◽

First Principles ◽

Open Shell

We report an ab initio study on the spectroscopy of the open-shell diatomic molecule yttrium oxide, YO.

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The structure and energetics of low-lying states of RCO and RNN free radicals

Canadian Journal of Chemistry ◽

10.1139/v77-120 ◽

1977 ◽

Vol 55 (5) ◽

pp. 863-868 ◽

Cited By ~ 20

Author(s):

N. Colin Baird ◽

Harish B. Kathpal

Keyword(s):

Experimental Data ◽

Free Radicals ◽

Hydrogen Atom ◽

Ab Initio ◽

Open Shell ◽

Basis Set ◽

Basis Sets ◽

Mo Calculations ◽

Decomposition Products ◽

Ab Initio Mo Calculations

The important geometrical variables in the structures of the lowest 2A′ and 2A′′ states of the free radicals HCO, CH3CO, NH2CO, HNN, and CH3NN have been determined by ab initio MO calculations using the STO-3G basis set. The energy differences between the states, and the energies of the radicals relative to their decomposition products and relative to their hydrogen atom addition products, are reported using both STO-3G and 4-31G basis sets in the restricted open-shell calculations. The trends in these results and their relation to available experimental data are discussed.

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Electronic Energy and Short-Range Order in Binary Alloys

MRS Proceedings ◽

10.1557/proc-19-53 ◽

1982 ◽

Vol 19 ◽

Author(s):

Mark O. Robbins ◽

L.M. Falicov

Keyword(s):

Transition Metals ◽

Total Energy ◽

Ab Initio ◽

Model Calculation ◽

Entire Range ◽

Short Range ◽

Short Range Order ◽

Binary Alloys ◽

Electronic Energy ◽

Range Order

ABSTRACTAn electronic theory for the total energy of binary alloys is presented. It treats the entire range of concentration and short-range order. The method in not ab initio, but requires only information about the pure elemental constituents of the alloy. Results for two very different metal series, monovalent metals and 4-d transition metals, are calculated and compared to experiment and other models. The model calculation allows us to examine the physical basis for experimental trends.

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