A correlation of excited state rotational constants for diatomic molecules

Rotational assignments are given for about 350 lines in the (0,9,0)–(0,0,0), (0,10,0)–(0,0,0), and (0,11,0)–(0,0,0) bands in the electronic absorption spectrum of NHD. The Σ and Δ sub-bands have been identified for the bands with ν2′ odd and the Π sub-band for the band with ν2′ even.Ground state rotational and spin–rotational constants have been determined. The principal constants in reciprocal centimetres are: A = 20.1162(32), B = 8.1114(16), C = 5.6681(16), εaa = −0.2324(51),εbb = −0.0373ε, εcc = −0.0019ε, where the error limits are 1σ. Term values are tabulated for both the ground and excited state levels.Several 'axis-switching' branches have been identified in agreement with the predictions of Hougen and Watson.

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A rapid method for determining excited state surface parameters and bond length in diatomic molecules and calculating wavefunctions for Franck-Condon factors using the quantum momentum method

Computers & Chemistry ◽

10.1016/0097-8485(91)80005-7 ◽

1991 ◽

Vol 15 (3) ◽

pp. 215-223

Author(s):

S.C. Lee ◽

Soo-Y. Lee

Keyword(s):

Excited State ◽

Bond Length ◽

Rapid Method ◽

Diatomic Molecules ◽

Surface Parameters ◽

Condon Factors ◽

Franck Condon

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Spectrum of azulene. IV. Rotational analysis of the 0-0 band of the 3500 Ǻ transition

Australian Journal of Chemistry ◽

10.1071/ch9682835 ◽

1968 ◽

Vol 21 (12) ◽

pp. 2835 ◽

Cited By ~ 31

Author(s):

AJ McHugh ◽

DA Ramsay ◽

IG Ross

Keyword(s):

Fine Structure ◽

Excited State ◽

Type A ◽

Resolving Power ◽

Rotational Analysis ◽

Type B ◽

Rotational Constants ◽

Multiple Line ◽

Asymmetric Top ◽

Low K

The bands of the 3500 Ǻ transition of azulene-do and azulene-ds show two unequal peaks 2.3 cm-l apart, followed by closely spaced fine structure. These bands have been analysed as type A bands of a planar, prolate asymmetric top. Rotational constants for both molecules in the excited state have been determined. The fine structure is due to multiple line coincidences in the high-J, low-K region of the qP branch. To each multiple line can be attributed a running number n = J+m, where m = J-K-1. Given sufficient resolving power, such "lines" should be rather commonly observed in type A and type B bands of large, planar, prolate molecules.

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Rotational and Vibrational Analysis of the First Singlet Transition (1B2 ← 1A1) of Isobenzofuran

Canadian Journal of Physics ◽

10.1139/p75-232 ◽

1975 ◽

Vol 53 (19) ◽

pp. 1814-1824 ◽

Cited By ~ 3

Author(s):

M. J. Robey ◽

I. G. Ross

Keyword(s):

Absorption Spectrum ◽

Excited State ◽

Vibrational Analysis ◽

Vibrational Structure ◽

Rotational Structure ◽

Type B ◽

State Structure ◽

Detailed Structure ◽

Rotational Constants ◽

Singlet Transition

The absorption spectrum of isobenzofuran vapor has been photographed at resolving powers in excess of 300 000. The vibrational structure is straightforward, involving totally symmetric vibrations only. The rotational structure of a band at 0 + 858 cm−1 has been analyzed as a type B band, leading to the assignment of the transition as 1B2 ← 1A1. The detailed structure of the band is described. The changes in the rotational constants are ΔA + 0.000124, ΔB −0.000122, and ΔC −0.00052 cm−1. A calculated excited state structure compatible with these results is proposed.

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Etude à basse température dans l'infrarouge proche du dimère (NO)2

Canadian Journal of Physics ◽

10.1139/p84-048 ◽

1984 ◽

Vol 62 (4) ◽

pp. 322-329 ◽

Cited By ~ 36

Author(s):

V. Menoux ◽

R. Le Doucen ◽

C. Haeusler ◽

J. C. Deroche

Keyword(s):

Excited State ◽

Gas Phase ◽

Ground State ◽

Near Infrared ◽

Heat Of Formation ◽

Wave Number ◽

Vibrational Modes ◽

Vibrationally Excited ◽

Rotational Constants ◽

Absorption Intensity

The spectrum of the dimer (NO)2 in the gas phase has been studied in the near infrared at temperatures between 118 and 138 K. More specifically, the measure of absorption intensity of the ν4 and ν1 + ν4 bands has yielded the heat of formation of the dimer, −2.25 kcal/mol at 128 K, and revealed the influence of the low vibrational modes on this measure. The observation of the ν4 – ν6, difference band has yielded the wave number value of the ν6, fundamental band, forbidden in the infrared. The rotational constants of the vibrationally excited state were found to be larger than the ground state rotational constants, this result being very unusual.

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Determination of excited-state rotational constants and structures by Doppler-free picosecond spectroscopy

The Journal of Physical Chemistry ◽

10.1021/j100352a014 ◽

1989 ◽

Vol 93 (15) ◽

pp. 5701-5717 ◽

Cited By ~ 51

Author(s):

J. Spencer Baskin ◽

Ahmed H. Zewail

Keyword(s):

Excited State ◽

Picosecond Spectroscopy ◽

Rotational Constants

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Rotational Spectrum of 2,3-Benzofuran

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20031572 ◽

2003 ◽

Vol 68 (9) ◽

pp. 1572-1578 ◽

Cited By ~ 1

Author(s):

B. Michela Giuliano ◽

Walther Caminati

Keyword(s):

Excited State ◽

Ground State ◽

Rotational Spectrum ◽

Frequency Range ◽

Supersonic Expansion ◽

Rotational Constants ◽

Millimetre Wave ◽

Rotational Spectra ◽

Wave Absorption ◽

Free Jet

The rotational spectra of the ground state and of one vibrational satellite of 2,3-benzofuran have been measured by millimetre-wave absorption free jet spectroscopy in the frequency range 60-78 GHz. The value of the inertial defect (-0.072 uÅ2) shows the molecule to be planar. The shifts of the rotational constants in going from the ground to the excited state indicate that the observed vibrational satellite does not belong to the two lowest energy motions, the butterfly and 1,3-ring-twisting, which undergo relaxation upon the supersonic expansion.

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