A vibration-rotation band of monodeuteromethane

1953 ◽  
Vol 216 (1125) ◽  
pp. 143-152 ◽  
Keyword(s):  
Energy Levels ◽  
High Dispersion ◽  
Vibration Band ◽  
Hydrogen Atoms ◽  
Vibrational States ◽  
Fundamental Vibration ◽  
Type Band ◽  
Vibration Rotation ◽  
Two Sides ◽  
Very High

The fundamental vibration band of monodeuteromethane near 4-5 μ , connected with the stretching of the C—D bond, has been reinvestigated with very high dispersion. It provides a good example of well-resolved parallel-type band structure of a symmetric top molecule in which the K splitting of P and R lines is clearly seen. Alternations of intensity are also found in accordance with the nuclear spin of the three hydrogen atoms. The rotational constants B 0 and B 1 have been determined, giving r 0 (C—H) = 1.0924Å. The centrifugal stretching coefficient D J and its variation in the different vibrational states have also been measured. Analysis of the K splitting of the R and P lines reveals an anomaly between the sets on the two sides of the band origin, which seems to suggest that some unforeseen molecular interaction is neglected in the method at present accepted for calculating the molecular rotational energy levels.

The fundamental vibration-rotation band of deuterium chloride

1953 ◽  
Vol 218 (1132) ◽  
pp. 37-43 ◽  
Keyword(s):  
Preceding Paper ◽  
Resolving Power ◽  
Vibration Band ◽  
Fundamental Vibration ◽  
Deuterium Chloride ◽  
Isotopic Molecule ◽  
Vibration Rotation ◽  
High Degree ◽  
Very High ◽  
Good Agreement

The fundamental vibration band of deuterium chloride near 5μ has been re-examined using much greater resolving power than previously. The isotopic splitting of the rotation lines has been completely resolved, and a greater number of lines has been measured in each of the branches forming the band. Rotational constants have been determined for the two combining states, and values have also been obtained for the centrifugal stretching constants. The relative values are in very good agreement with those to be expected for a pair of isotopic molecules with the atomic masses concerned. The new value (1·274 6 Å) derived for the bond length in both species of deuterium chloride agrees to a very high degree with that found in the preceding paper for the isotopic molecule hydrogen chloride.

Vibration-rotation bands and rotational constants of dideuteroacetylene

1955 ◽  
Vol 232 (1190) ◽  
pp. 291-309 ◽  
Keyword(s):  
Resolving Power ◽  
Vibrational States ◽  
Absorption Bands ◽  
Rotational Constants ◽  
Vibrational Assignments ◽  
Vibrational Anharmonicity ◽  
A Value ◽  
Vibrational Levels ◽  
Vibration Rotation ◽  
Very High

Nine vibrational absorption bands of dideutero-acetylene have been examined with very high resolving power. The rotational constants have been determined for the vibrational levels concerned, and the coefficients α i have been determined with more convincing accuracy than previously. In some of the bands the Q branches have been resolved, so that the l -doubling coefficients q i could be derived, and details could be established about the doublet components in some II levels. The results emphasize the need of high resolution if the vibrational assignments are to be unambiguous, and if reliable values of the rotational constants are to be derived. A value of B e has been obtained, and the vibrational anharmonicity coefficients have been considered briefly. Estimates of the centrifugal stretching constants D i in different vibrational states have been made, and one anomalous case has been found.

A spectroscopic study of HCP, the phosphorus analogue of hydrocyanic acid

1969 ◽  
Vol 47 (8) ◽  
pp. 893-920 ◽  
Author(s):  
J. W. C. Johns ◽  
H. F. Shurvell ◽  
J. K. Tyler
Keyword(s):  
Energy Levels ◽  
Hydrocyanic Acid ◽  
Ultraviolet Absorption Spectrum ◽  
Triplet States ◽  
Fundamental Vibration ◽  
Excited Triplet ◽  
Singlet States ◽  
State Formula ◽  
Excited Singlet States ◽  
Vibration Rotation

The ultraviolet absorption spectrum of HCP has been observed from 4100 Å to about 2350 Å, and seven electronic transitions have been identified. Three of these transitions involve excited singlet states and four of them involve excited triplet states. The symmetries, energies, and equilibrium conformations of these states are listed below:[Formula: see text]Some observations have also been made on the vibration–rotation energy levels of the ground electronic state, [Formula: see text], of HCP. The fundamental vibration frequencies (in cm−1) are ν1 = 3216.9, ν2 = 674.7, and ν3 = 1278.4.

Determinable parameters of the effective rotational Hamiltonians for excited vibrational states of semirigid symmetric top molecules of C4v, D4, D2h, andD2d symmetry

1989 ◽  
Vol 54 (12) ◽  
pp. 3107-3116
Author(s):  
Kamil Sarka ◽  
Dušan Papoušek
Keyword(s):  
Symmetry Axis ◽  
Energy Levels ◽  
Contact Transformation ◽  
Centrifugal Distortion ◽  
Vibrational States ◽  
Fourfold Symmetry ◽  
Vibration Rotation ◽  
Symmetric Top Molecules ◽  
Rotation Energy ◽  
General Method

A general method is described for obtaining the S functions which in the contact transformation of the vibration-rotation Hamiltonian of semirigid molecules with the fourfold symmetry axis eliminate the rotational and vibrational l-type operators and the Δk = ±4 centrifugal distortion operators from the λH1 terms of the expanded Hamiltonian. Explicit expressions are given for the vibration-rotation energy levels with independent effective spectroscopic parameters. Expressions are also given for the splittings of energy levels with essential resonances.

Vibration-rotation bands of methyl fluoride and methyl fluoride- d 3

1966 ◽  
Vol 290 (1423) ◽  
pp. 490-507 ◽  
Keyword(s):  
Energy Levels ◽  
Molecular Constants ◽  
Methyl Halides ◽  
Methyl Fluoride ◽  
Rotational Constants ◽  
Vibrational Levels ◽  
Vibration Rotation ◽  
Two Sides ◽  
Unusual Type

Four parallel vibration-rotation bands of CD 3 F have been measured, and much of their fine structure has been resolved. In some of these bands, the K splitting of the central Q branches has been measured, and in one case the P and B lines of the subbands, corresponding to different K values, have been analysed. Eight perpendicular type bands of CD 3 F have been measured, and seven have been analysed. One of these, v 4 , shows much P-R structure of the subbands. Values have been derived for the rotational constants, Coriolis coefficients, and the α values which relate the rotational constants in different vibrational levels. The value found for A o is 2.56 1 cm -1 . One parallel and two perpendicular bands of methyl fluoride have been analysed, and the results have been considered with previous data on this molecule to estimate the molecular constants. The band v 5 shows an unusual type of perturbation which appears to affect the two sides of the band in different ways. The value found for A 0 is 5.08 1 cm -1 . The results show again, as found with other methyl halides, that interactions between energy levels often lead to perturbations which complicate the determination of the molecular constants.

scholarly journals The Application of Electromagnetic Sensors for Determination of Cherenkov Cone Inside and in the Vicinity of the Detector Volume in Any Environment Known

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 992
Author(s):  
Valeriu Savu ◽  
Mădălin Ion Rusu ◽  
Dan Savastru
Keyword(s):  
Energy Levels ◽  
Cherenkov Detector ◽  
Electromagnetic Sensors ◽  
The Cost ◽  
Information Errors ◽  
The Universe ◽  
Large Frequency ◽  
Very High ◽  
Detector Volume

The neutrinos of cosmic radiation, due to interaction with any known medium in which the Cherenkov detector is used, produce energy radiation phenomena in the form of a Cherenkov cone, in very large frequency spectrum. These neutrinos carry with them the information about the phenomena that produced them and by detecting the electromagnetic energies generated by the Cherenkov cone, we can find information about the phenomena that formed in the universe, at a much greater distance, than possibility of actually detection with current technologies. At present, a very high number of sensors for detection electromagnetic energy is required. Thus, some sensors may detect very low energy levels, which can lead to the erroneous determination of the Cherenkov cone, thus leading to information errors. As a novelty, we propose, to use these sensors for determination of the dielectrically permittivity of any known medium in which the Cherenkov detector is used, by preliminary measurements, the subsequent simulation of the data and the reconstruction of the Cherenkov cone, leading to a significant reduction of problems and minimizing the number of sensors, implicitly the cost reductions. At the same time, we offer the possibility of reconstructing the Cherenkov cone outside the detector volume.

scholarly journals Modelling the atmosphere of lava planet K2-141b: implications for low- and high-resolution spectroscopy

2020 ◽  
Vol 499 (4) ◽  
pp. 4605-4612
Author(s):  
T Giang Nguyen ◽  
Nicolas B Cowan ◽  
Agnibha Banerjee ◽  
John E Moores
Keyword(s):  
Steady State ◽  
Ocean Circulation ◽  
Scale Height ◽  
High Resolution Spectroscopy ◽  
Return Flow ◽  
High Dispersion ◽  
Magma Ocean ◽  
Steady State Flow ◽  
Wide Range ◽  
Very High

ABSTRACT Transit searches have uncovered Earth-size planets orbiting so close to their host star that their surface should be molten, so-called lava planets. We present idealized simulations of the atmosphere of lava planet K2-141b and calculate the return flow of material via circulation in the magma ocean. We then compare how pure Na, SiO, or SiO2 atmospheres would impact future observations. The more volatile Na atmosphere is thickest followed by SiO and SiO2, as expected. Despite its low vapour pressure, we find that a SiO2 atmosphere is easier to observe via transit spectroscopy due to its greater scale height near the day–night terminator and the planetary radial velocity and acceleration are very high, facilitating high dispersion spectroscopy. The special geometry that arises from very small orbits allows for a wide range of limb observations for K2-141b. After determining the magma ocean depth, we infer that the ocean circulation required for SiO steady-state flow is only 10−4 m s−1, while the equivalent return flow for Na is several orders of magnitude greater. This suggests that a steady-state Na atmosphere cannot be sustained and that the surface will evolve over time.

Infrared spectra, rotational correlation functions, and intermolecular mean squared torques in compressed gaseous methane

1968 ◽  
Vol 46 (11) ◽  
pp. 1331-1340 ◽  
Author(s):  
R. L. Armstrong ◽  
S. M. Blumenfeld ◽  
C. G. Gray
Keyword(s):  
Correlation Functions ◽  
Theoretical Calculations ◽  
Dominant Contribution ◽  
Dispersion Interactions ◽  
Fundamental Vibration ◽  
Order Of Magnitude ◽  
The Mean ◽  
Vibration Rotation ◽  
Experimental Values ◽  
Rotational Correlation

Extensive measurements of the methane ν3 and ν4 fundamental vibration–rotation bands in CH4–He mixtures and the ν3 band in CH4–He, CH4–N2, and CD4–He mixtures have been carried out in infrared absorption at 295 °K to pressures of 3000 atm. Some profiles of the ν3 band in CH4–Ar mixtures and in pure CH4 have also been obtained. Rotational correlation functions, band moments, and intermolecular mean squared torques have been determined from the ν3 band profiles. Theoretical calculations of the mean squared torque due to anisotropic multipolar, induction and dispersion interactions have been carried out. The theoretical and experimental torques are in order-of-magnitude agreement for the CH4–N2 and CH4–CH4 systems; for CH4–He, CD4–He, and CH4–Ar the theoretical values are two to three orders of magnitude too small to account for the experimental values, indicating that in these cases the dominant contribution to the torques is given by the anisotropic overlap forces.

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