J/ApJ/717/674 Ionization energies of CnN(n=4-12) (Kostko+, 2010)
Determination of ionization energies of CnN (n = 4-12): vacuum ultraviolet
photoionization experiments and theoretical calculations.
Kostko O., Zhou J., Sun B.J., Lie J.S., Chang A.H.H., Kaiser R.I.,
Ahmed M.
<Astrophys. J., 717, 674-682 (2010)>
=2010ApJ...717..674K 2010ApJ...717..674K
ADC_Keywords: Atomic physics ; Interstellar medium
Keywords: astrochemistry - ISM: molecules - methods: laboratory -
molecular data - techniques: spectroscopic
Abstract:
Results from single photon vacuum ultraviolet photoionization of
astrophysically relevant CnN clusters, n=4-12, in the photon energy
range of 8.0eV-12.8eV are presented. The experimental photoionization
efficiency curves, combined with electronic structure calculations,
provide improved ionization energies of the CnN species. A search
through numerous nitrogen-terminated CnN isomers for n=4-9 indicates
that the linear isomer has the lowest energy, and therefore should be
the most abundant isomer in the molecular beam. Comparison with
calculated results also shed light on the energetics of the linear
CnN clusters, particularly in the trends of the even-carbon and the
odd-carbon series. These results can guide the search of potential
astronomical observations of these neutral molecules together with
their cations in highly ionized regions or regions with a high UV/VUV
photon flux (ranging from the visible to VUV with flux maxima in the
Lyman-α region) in the interstellar medium.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 66 231 Calculated energies of various isomers of
CnN (n=1-14)
table3.dat 322 117 Vibrational frequencies and rotational constants
of CnN (n=3-14) isomers calculated with
B3LYP/cc-pVTZ
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See also:
VI/74 : Atomic Energy Level Data (NIST 1993)
J/ApJ/688/L83 : Detection of C5N- in IRC +10216 (Cernicharo+, 2008)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Mol Molecular identification (1)
12- 21 A10 --- Term Term symbol (2)
22- 32 F11.6 2Ry UB3LYP ? B3LYP/cc-pVTZ energy; in Hartree (3)
34- 41 F8.6 2Ry ZPE ? Zero-point energy by B3LYP/cc-pVTZ; in Hartree
43- 54 F12.7 2Ry CCSD(T) ? CCSD(T)/cc-pVTZ energy; in Hartree
56- 60 F5.2 eV IE-B ? Ionization energy by B3LYP/cc-pVTZ (3)
62- 66 F5.2 eV IE-C ? Ionization energy by CCSD(T)/cc-pVTZ (3)
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Note (1): Notes in the "()"s as follows:
3 = Geometry optimization by CASSCF(5,5)/cc-pVTZ.
4 = Geometry optimization by CASSCF(4,4)/cc-pVTZ.
5 = Geometry optimization by CASSCF(4,5)/cc-pVTZ.
6 = Geometry optimization by ROHF/6-31G*.
Note (2): The term symbols of the doublet neutral states, the singlet
cation states and the triplet cation states are listed when available.
(TeX notation for greek letter)
Note (3): With B3LYP/cc-pVTZ zero-point energy correction.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Mol Molecule name (1)
12-295 A284 cm-1 VFreq Vibrational frequencies
297-322 A26 GHz RotCon Rotational constants
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Note (1): Listed in the order of doublet neutral state, singlet cation
state, and triplet cation state.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 05-Jun-2012