The a″ vibrations of singlet propynal

1993 ◽  
Vol 71 (10) ◽  
pp. 1556-1561 ◽  
Author(s):  
J.K.G. Watson
Keyword(s):  
Electronic State ◽  
Band System ◽  
Excited Electronic State ◽  
Vibrational Frequencies ◽  
Ground Electronic State ◽  
Harmonic Potential

The a″ vibrational frequencies of all possible H and D isotopomers of propynal (HCCCHO) are shown to allow two solutions for the a″ harmonic potential constants. Equations relating the solutions are given. In the [Formula: see text] ground electronic state one solution can be rejected as chemically unrealistic, but in the [Formula: see text] excited electronic state the choice is more difficult. It is shown that a choice can be made on the basis of the observed cross-sequence intensities in the [Formula: see text] band system.

Formation of NaH Molecules in the Lowest Rovibrational Level of the Ground Electronic State via Short-Range Photoassociation

2014 ◽  
Vol 17 (1) ◽  
pp. 79-92 ◽  
Author(s):  
Jinglun Li ◽  
Yin Huang ◽  
Ting Xie ◽  
Shuo Chai ◽  
Shulin Cong
Keyword(s):  
Electric Field ◽  
Electronic State ◽  
Pulse Duration ◽  
Delay Time ◽  
Short Range ◽  
Excited Electronic State ◽  
Laser Pulses ◽  
Ground Electronic State ◽  
High State ◽  
State Selectivity

AbstractThe formation of NaH molecules in the lowest rovibrational level of the ground electronic state is investigated using a pump-dump photoassociation (PA) scheme. In short-range region, two colliding atoms Na and H are efficiently associated into the NaH molecule in the rovibrational |0,0〉 state of the ground electronic state via the intermediately rovibrational |10,1〉 state of the excited electronic state. The changes of populations with the electric field amplitudes, frequency detunings, dump pulse duration and delay time between two laser pulses are calculated and discussed. The PA probability reaches 0.623 with a high state-selectivity.

scholarly journals Precision measurement of the fundamental vibrational frequencies of tritium-bearing hydrogen molecules: T2, DT, HT

2020 ◽  
Vol 22 (16) ◽  
pp. 8973-8987 ◽  
Author(s):  
K.-F. Lai ◽  
V. Hermann ◽  
T. M. Trivikram ◽  
M. Diouf ◽  
M. Schlösser ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
High Resolution ◽  
Electronic State ◽  
Precision Measurement ◽  
Molecular Hydrogen ◽  
Vibrational Frequencies ◽  
Ground Electronic State ◽  
Hydrogen Molecules ◽  
Coherent Raman

High-resolution coherent Raman spectroscopy of all three tritium-containing molecular hydrogen – T2, DT and HT – were performed to determine the ground electronic state fundamental Q-branch transition frequencies at accuracies of 0.0005 cm−1.

THE 1600 Å BAND SYSTEM OF AMMONIA

1961 ◽  
Vol 39 (4) ◽  
pp. 479-501 ◽  
Author(s):  
A. E. Douglas ◽  
J. M. Hollas
Keyword(s):  
Excited State ◽  
High Resolution ◽  
Electronic State ◽  
Band System ◽  
Excited Electronic State ◽  
Degenerate State ◽  
Coriolis Interaction ◽  
Plane Vibration ◽  
Vibrational Levels ◽  
Out Of Plane

The progression of ammonia bands which extends from 1689 to 1400 Å has been photographed in absorption at high resolution. Six bands have been analyzed and found to be of the perpendicular type. The analysis shows that the molecule is planar in the excited state and that vibrational levels observed in the progression are those of the out-of-plane vibration. The excited electronic state is of the E′′ type. In addition to the normal Coriolis interaction of the degenerate levels, a second effect has been observed which behaves like the Coriolis interaction recently described as 'giant l-type doubling' by Garing, Nielsen, and Rao. No clear evidence has been found for any distortion of the degenerate state from D3h symmetry.

FORMATION OF ULTRACOLD CESIUM MOLECULES IN THE GROUND ELECTRONIC STATE

2012 ◽  
Vol 11 (06) ◽  
pp. 1323-1330 ◽  
Author(s):  
XUE-JIN HU ◽  
WEI ZHANG ◽  
YIN HUANG ◽  
JUN-FENG YANG ◽  
SHU-LIN CONG
Keyword(s):  
Electronic State ◽  
Excited Electronic State ◽  
Grid Method ◽  
Laser Pulses ◽  
Time Dependent ◽  
Ground Electronic State ◽  
Adiabatic Passage ◽  
Stimulated Raman Adiabatic Passage ◽  
Chirped Laser Pulse ◽  
Partial Population

We investigate theoretically the preparation of ultracold photoassociated Cs 2 molecules in the lowest vibrational level of the ground electronic state via the stimulated Raman adiabatic passage (STIRAP) by solving the time-dependent Schrödinger equation using the mapped Fourier grid method. A negative chirped laser pulse is used to produce the unstable photoassociated molecules in the excited electronic state. A dump pulse is utilized to transfer a partial population of the unstable photoassociated molecules to the vibrational v″ = 18 level of the ground electronic state. This part of population is then transferred to the v″ = 0 level of the ground electronic state by the pump and Stokes laser pulses via an intermediate state which is taken to be the v′ = 7 level of the excited electronic state, forming the stable photoassociated molecules. The population transfer efficiency from v″ = 18 to v″ = 0 in the ground electronic state reaches 96.2% via the STIRAP.

Variational Method for Estimating the Dipole Moment in the Second Excited State of Fluorescein Molecule from its Electronic UV Absorption Spectra

2019 ◽  
Vol 70 (10) ◽  
pp. 3538-3544
Author(s):  
Alina Costina Luca ◽  
Ana Cezarina Morosanu ◽  
Irina Macovei ◽  
Dan Gheorghe Dimitriu ◽  
Dana Ortansa Dorohoi ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Excited State ◽  
Variational Method ◽  
Electronic State ◽  
Excited Electronic State ◽  
Spectral Band ◽  
Uv Absorption ◽  
Optical Parameters ◽  
Electrical Permittivity ◽  
Fluorescein Molecule

Electro-optical parameters of fluorescein molecule in the second excited electronic state and information on the interactions with solvents were obtained from a solvatochromic study. Parameters of the solvents such as the refractive index, electrical permittivity and Kamlet-Taft parameters (hydrogen bond acidity and basicity) were related with the experimentally recorded shifts of UV absorption spectral band of fluorescein dissolved in several solvents. Through a variational method, the electric dipole moment and polarizability in excited state of fluorescein molecule were estimated. The calculus requires some parameters of the fluorescein molecule in the ground electronic state, which were determined through a quantum-mechanical study.

scholarly journals The flame spectrum of carbon monoxide

1940 ◽  
Vol 176 (967) ◽  
pp. 505-521 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Electronic State ◽  
Excited Electronic State ◽  
Combustion Process ◽  
Wave Number ◽  
Band Spectrum ◽  
Liquid Form ◽  
Triangular Form ◽  
Reduced Pressure

The spectrum of the flame of carbon monoxide burning in air and in oxygen at reduced pressure has been photographed on plates of high contrast which display the band spectrum clearly above the continuous background. Greater detail has been obtained than has been recorded previously and new measurements are given. The structure of the spectrum has been studied systematically. It is shown that the bands occur in pairs with a separation of about 60 cm. -1 , this separation being due probably to the rotational structure. Various wave-number differences are found to occur frequently, and many of the strong bands are arranged in arrays using intervals of 565 and 2065 cm. -1 . The possible origin of the spectrum is discussed. The choice of emitter is limited to a polyatomic oxide of carbon, of which carbon dioxide is the most likely. The spectrum of the suboxide C 3 O 2 shows some resemblance to the flame bands, but this molecule is improbable as the emitter on other grounds. A peroxide C0 3 is also a possibility, but no evidence for the presence of this has been obtained from experiments on the slow combustion of carbon monoxide. Carbon dioxide in gaseous or liquid form is transparent through the visible and quartz ultra-violet, and the flame bands are not obtained from CO 2 in discharge tubes. Comparison with the Schumann-Runge bands of oxygen shows that it is possible that the flame bands may form part of the absorption band system of CO 2 which is known to exist below 1700 A if there is a big change in shape or size of the molecule in the two electronic states. The electronic energy levels of CO 2 are discussed. Since normal CO 2 is not built up from normal CO and oxygen, an electronic rearrangement of the CO 2 must occur after the combustion process. Mulliken has suggested that the molecule in the first excited electronic state, corresponding to absorption below 1700 A, may have a triangular form. The frequencies obtained from the flame bands are compared with the infra-red frequencies of CO 2 . The 565 interval may be identified with the transverse vibration v 2 , indicating that the excited electronic state is probably triangular in shape. The 2065 interval cannot, however, be identified with the asymmetric vibration v 3 with any certainty. If the excited electronic state of CO 2 is triangular, then molecules formed during the combustion by transitions from this level to the ground state may be “vibrationally activated”. This is probably the reason for many of the peculiarities of the combustion of carbon monoxide.

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