The infrared spectrum of aminodifluoroborane, NH2BF2: Partial assignment of the fundamentals and analysis of the band near 1608 cm−1

1988 ◽  
Vol 66 (8) ◽  
pp. 2088-2099 ◽  
Author(s):  
H. M. Jemson ◽  
W. Lewis-Bevan ◽  
M. C. L. Gerry
Keyword(s):  
Infrared Spectrum ◽  
Gas Phase ◽  
Spectroscopic Constants ◽  
Centrifugal Distortion ◽  
Coriolis Interaction ◽  
Partial Assignment ◽  
Rotational Perturbation ◽  
Band Origin ◽  
Centrifugal Distortion Constants ◽  
First Time

The infrared spectrum of gas phase aminodifluoroborane, NH2BF2, has been observed for the first time. A partial assignment to the fundamental vibrations has been made. The [Formula: see text] band has been recorded at high resolution, and the rotational and centrifugal distortion constants of NH211F2 have been obtained in both the ground and 21 levels. A small rotational perturbation in the 21 level has been attributed to a perpendicular Coriolis interaction. Using a newly written least-squares fitting program, spectroscopic constants of the unseen level have been evaluated, including its band origin and the Coriolis coupling coefficient. Possible identities of the unseen level are suggested.

Infrared spectrum of the fundamental ν1 of deutero-isocyanic acid

1981 ◽  
Vol 59 (10) ◽  
pp. 1313-1326 ◽  
Author(s):  
D. A. Steiner ◽  
S. R. Polo ◽  
T. K. McCubbin Jr. ◽  
K. A. Wishah
Keyword(s):  
High Resolution ◽  
Infrared Spectrum ◽  
Isocyanic Acid ◽  
Centrifugal Distortion ◽  
Rotational Constants ◽  
Fundamental Band ◽  
Band Origin ◽  
Stretching Vibration ◽  
Centrifugal Distortion Constants ◽  
First Time

The ν1 fundamental band of DNCO has been observed for the first time under high resolution. The band origin for this deuterium–nitrogen stretching vibration is found to be at 2637.198 cm−1, rather distant from the previously reported value of 2634.9 cm−1. Eighteen subbands have been analyzed and term values for both ground and ν1 states with K up to 6 have been obtained. Effective rotational constants Bν and centrifugal distortion constants Dν and Hν have also been determined. Interaction is observed with the 2ν3 vibration which has a band origin around 2640 cm−1. Interesting perturbations are observed for the K = 0 and K = 4 levels of ν1.

Infrared spectrum of HNCO between 8 and 80 cm−1

1984 ◽  
Vol 62 (12) ◽  
pp. 1452-1466 ◽  
Author(s):  
L. Fusina ◽  
M. Carlotti ◽  
B. Carli
Keyword(s):  
Infrared Spectrum ◽  
Ground State ◽  
Far Infrared ◽  
Spectroscopic Constants ◽  
Centrifugal Distortion ◽  
Excited Vibrational State ◽  
Millimetre Wave ◽  
Band Origin ◽  
Centrifugal Distortion Constants ◽  
Infrared Data

The infrared spectrum of isocyanic acid, HNCO, has been recorded in the range 8–80 cm−1 with a resolution of about 0.004 cm−1a-type and b-type rotational transitions have been measured and assigned in the ground state and in the ν4 = 1, ν5 = 1, ν6 = 1, and ν5 = 2 vibrational states.Improved values of the ground state rotational and centrifugal distortion constants in the Ir S-reduced Hamiltonian of Watson have been obtained in a simultaneous analysis of our measurements and microwave, millimetre-wave, and far infrared data reported previously. Sub-band origins and effective spectroscopic constants have been determined for each excited vibrational state. An accurate value for the ν6 band origin, at 656.287 cm−1, has been deduced.

scholarly journals Infrared spectrum of the CH3OH – CO complex in the C–O stretching region

2001 ◽  
Vol 79 (2-3) ◽  
pp. 461-466
Author(s):  
C Xia ◽  
A RW McKellar
Keyword(s):  
Carbon Monoxide ◽  
Infrared Spectrum ◽  
Gas Phase ◽  
Blue Shift ◽  
Weakly Bound ◽  
Band Origin ◽  
Simulation Based ◽  
Stretching Vibration ◽  
First Time ◽  
Rotation Component

The infrared spectrum of the weakly-bound molecular complex methanol - carbon monoxide has been observed, for the first time in the gas phase, by means of a parallel (Δ K = 0) band in the region of the carbon monoxide C–O stretching vibration. The band origin, 2154.5 cm–1, represents a blue shift of 11.2 cm–1 relative to the free CO molecule; its proximity to that of the H2O – CO complex points to a similarity of the hydrogen bonding in the two systems. The observed structure of the band could be well reproduced by a simulation based on the methyl internal rotation component of A-symmetry. A component of E-symmetry must also be present, with roughly equal intensity, but the two components were not individually resolved. The observed transitions showed evidence of predissociation broadening, leading to an estimate of t [Formula: see text] 0.5 ns for the lifetime of the upper (C–O stretching) state.PACS Nos.: 3320E, 3425, 3520P, 3640

Detection of the Infrared Spectrum of Cyanobutadiyne, HC5N

1981 ◽  
Vol 36 (10) ◽  
pp. 1052-1056 ◽  
Author(s):  
Koichi Yamada ◽  
Gisbert Winnewisser
Keyword(s):  
Infrared Spectrum ◽  
Diode Laser ◽  
Vibrational State ◽  
Tunable Diode Laser ◽  
Centrifugal Distortion ◽  
Laser Spectrometer ◽  
Excited Vibrational State ◽  
Diode Laser Spectrometer ◽  
Band Origin ◽  
Centrifugal Distortion Constants

The CN stretching band, ν2, of cyanobutadiyne has been detected by a tunable diode laser spectrometer in the wavenumber range from 2250 to 2260 cm-1. The P-and R-branch transitions, up to P(77) and R(75), of the fundamental band were identified and measured with the accuracy of 0.001 cm-1. The band origin was obtained to be 2256.12406(13) cm-1. The rotational and centrifugal distortion constants in the excited vibrational state, B′ and D′, were also determined.

Ground state spectroscopic constants and electric dipole moment of D14N12C32S from its microwave and millimetre wave spectra

1978 ◽  
Vol 56 (10) ◽  
pp. 1297-1307 ◽  
Author(s):  
L. B. Szalanski ◽  
M. C. L. Gerry ◽  
G. Winnewisser ◽  
K. Yamada ◽  
M. Winnewisser
Keyword(s):  
Dipole Moment ◽  
Stark Effect ◽  
Coupling Constants ◽  
Spectroscopic Constants ◽  
Wave Spectra ◽  
Centrifugal Distortion ◽  
Millimetre Wave ◽  
Quadrupole Coupling ◽  
Centrifugal Distortion Constants ◽  
First Time

The microwave and millimetre wave spectra of D14N12C32S in its ground vibrational state have been investigated in the frequency region 8–210 GHz. A large number of a-type Q branch and b-type P and R branch transitions up to J = 62 have been assigned and measured for the first time. Their frequencies have been combined with those of the a-type R branches up to K = 5 in an analysis for rotational, centrifugal distortion, and 14N quadrupole coupling constants. Constants obtained, in Watson's S reduction formalism, are: rotational constants in megahertz: A0 = 705 511(370); B0 = 5500.4391(15); C0 = 5445.2252(15); quartic centrifugal distortion constants in kilohertz: Dj = 1.0926(25); Djk = 1333.4(12); d1 = 3.455(5) × 10−2d2 = −7.8(14) × 10−3; 14N quadrupole coupling constants in megahertz: χaa = 1.19(6), χbb−χcc <0.05. The b-component of the dipole moment, μb, has been measured using the Stark effect as 1.08(15) D; this, when combined with μa = 1.67(3) D gives a total dipole moment of 1.99(15) D, essentially parallel to the HN bond.

The Centrifugally Induced Pure Rotational Spectrum and the Structure of Sulfur Trioxide. A Microwave Fourier Transform Study of a Nonpolar Molecule

1991 ◽  
Vol 46 (8) ◽  
pp. 710-714 ◽  
Author(s):  
Volker Meyer ◽  
Dieter Hermann Sutter ◽  
Helmut Dreizler
Keyword(s):  
Fourier Transform ◽  
Sulfur Trioxide ◽  
Rotational Spectrum ◽  
Centrifugal Distortion ◽  
Rotational Constants ◽  
Nonpolar Molecule ◽  
Centrifugal Distortion Constants ◽  
First Time

AbstractThe pure rotational spectrum of sulfur trioxide has been observed for the first time. A total of 25 high-J transitions could be assigned. The rotational constants, two quartic centrifugal distortion constants, and three sextic centrifugal distortion constants were determined as: B= 10 449.0667(23) MHz, C = 5216.0330(12) MHz, DJ = 9.2651 (18) kHz, DJK = -16.3922(18) kHz, HJ, = -8.8(34) • 10-3 Hz, HJK= -15.8(73) • 10-3 Hz, and HKJ = 34.2(73) • 10-3 Hz. An r0- and an re -structure are presented: r0= 1.4198(7) Å (calculated from B), r0 = 1.4210(7) Å (calculated from C), and re = 1.4175 Å

High-Resolution Infrared Spectrum of Diazirine, H2CN2. Rovibrational Analysis of the Methylene Deformation Band

1988 ◽  
Vol 43 (4) ◽  
pp. 331-337 ◽  
Author(s):  
A. Gambi ◽  
A. Baldacci ◽  
S. Giorgianni
Keyword(s):  
Fourier Transform ◽  
High Resolution ◽  
Infrared Spectrum ◽  
Least Squares ◽  
Deformation Band ◽  
Fourier Transform Spectrometer ◽  
Centrifugal Distortion ◽  
Molecular Constants ◽  
Centrifugal Distortion Constants

Abstract The infrared spectrum of diazirine has been recorded at Doppler resolution with a high informa­tion Fourier transform spectrometer. The ν3 fundamental has been reinvestigated and the overall assignment of the rovibrational transitions has been carried out. From the least-squares analysis a more accurate set of molecular constants including the sextic centrifugal distortion constants has been determined for the level υ3 = 1 and will be reported here. The higher resolution achieved here allowed the assignment of weaker lines and many Q branch transitions. Moreover many blended lines have now been resolved and could be properly assigned.

scholarly journals Accurate rest frequencies for propargylamine in the ground and low-lying vibrational states

2018 ◽  
Vol 615 ◽  
pp. A176 ◽  
Author(s):  
C. Degli Esposti ◽  
L. Dore ◽  
C. Puzzarini ◽  
M. Biczysko ◽  
J. Bloino ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Organic Molecules ◽  
Coupling Constants ◽  
Spectroscopic Constants ◽  
Rotational Spectrum ◽  
Centrifugal Distortion ◽  
Vibrational States ◽  
Important Species ◽  
Centrifugal Distortion Constants ◽  
High Level

Context. To date, several complex organic molecules have been detected in the interstellar medium, and they have been suggested as precursors of biologically important species. Propargylamine (HC ≡C−CH2−NH2) is structurally similar to a number of other organic molecules which have already been identified by radioastronomy, making it a good candidate for astrophysical detection. Aims. This work provides accurate rest frequencies of propargylamine, from the centimeter-wave to the submillimeter-wave region, useful to facilitate the detection of this molecule in the interstellar medium. Methods. An extensive laboratory study of the rotational spectrum of propargylamine has been performed using a pulsed-jet Fourier Transform Microwave (FTMW) spectrometer (7–19 GHz frequency range) and a frequency modulation microwave spectrometer (75–560 GHz). Several hundred rotational transitions of propargylamine were recorded in the ground and three lowest excited vibrational states. The experiments were supported by high-level ab initio computations, mainly employed to characterize the vibrational state structure and to predict spectroscopic parameters unknown prior to this study. Results. The measured transition frequencies yielded accurate rotational constants and the complete sets of quartic and sextic centrifugal distortion constants for propargylamine in its vibrational ground state. 14N-nuclear quadrupole coupling constants were also determined. Rotational and quartic centrifugal distortion constants were also obtained for the low-lying excited states v13 = 1 (A′), v20 = 1 (A″), and v21 = 1 (A″). The a-type Coriolis resonance which couples the v13 = 1 and v21 = 1 levels was analyzed. Conclusions. The determined spectroscopic constants allowed for the compilation of a dataset of highly accurate rest frequencies for astrophysical purposes in the millimeter and submillimeter regions with 1σ uncertainties that are smaller than 0.050 MHz, corresponding to 0.03 km s−1 at 500 GHz in radial equivalent velocity.

Mikrowellenspektrum und rotationsspektroskopische Konstanten der Methylchlorsilane: CH3SiH2Cl, CH3SiD2Cl und CD3SiD2Cl / Microwave Spectrum and Rotational Spectroscopic Constants of Methyl-chloro-silane: CH3SiH2Cl, CH3SiD2Cl and CD3SiD2Cl

1975 ◽  
Vol 30 (11) ◽  
pp. 1441-1446
Author(s):  
W. Zeil ◽  
W. Braun ◽  
B. Haas ◽  
H. Knehr ◽  
F. Rückert ◽  
...  
Keyword(s):  
Microwave Spectrum ◽  
Coupling Constants ◽  
Spectroscopic Constants ◽  
Centrifugal Distortion ◽  
Rotational Constants ◽  
Microwave Spectra ◽  
Isotopic Species ◽  
Quadrupole Coupling ◽  
Nuclear Quadrupole ◽  
Centrifugal Distortion Constants

The microwave spectra of the following isotopic species of Methyl-chloro-silane: CH3SiH2Cl, CH3SiD2 and CD3SiD2Cl have been measured and the rotational spectroscopic constants (rotational constants, centrifugal distortion constants and nuclear quadrupole coupling constants) have been determined

High-resolution Fourier transform study of the ν11 and ν7 fundamentals of cyclopropane

1984 ◽  
Vol 62 (12) ◽  
pp. 1369-1373 ◽  
Author(s):  
Josef Pliva ◽  
J. W. C. Johns
Keyword(s):  
Fourier Transform ◽  
High Resolution ◽  
Spectroscopic Constants ◽  
Hamiltonian Matrix ◽  
Matrix Elements ◽  
Vibrational States ◽  
Coriolis Interaction ◽  
Band Origin ◽  
The Matrix ◽  
Parallel Band

The absorption spectrum of cyclopropane, C3H6, was measured in the region between 790 and 950 cm−1 on a high-resolution Fourier transform spectrometer. The section containing the Q-branches of the perpendicular band of the ν11 vibration of species E′ was deconvolved to an effective line width of 0.0020–0.0025 cm−1. The structure of the ν11 band is strongly affected by l-type resonance. A total of 88 sub-bands with KΔK = −42 to 45 have been assigned in this band. The K = 4–3 and 2–3 sub-bands both exhibit K doubling of the lines with high J resulting from a combined effect of the off-diagonal matrix elements [Formula: see text], [Formula: see text], and [Formula: see text] with the l doubling in the K = 1, l = 1 state. Otherwise, the ν11 band is found to be free of perturbations by other vibrational states, in spite of the fact that a Jx,y Coriolis interaction is allowed by selection rules with the ν7 band (species [Formula: see text]) whose band origin is only 14.38 cm−1 below that of ν11. This shows that the value of [Formula: see text] is essentially zero. Also, the allowed Jz Coriolis interaction with the ν10 state, which lies 160.01 cm−1 above ν11, does not noticeably affect the two bands. A Hamiltonian matrix, including the matrix elements responsible for the K doubling and l-type resonance, was used for the treatment of the ν11 band. A set of accurate ground state constants and spectroscopic constants for the upper state ν11 is reported that reproduces 3240 observed lines of this band with a standard deviation of 0.0009 cm−1. Lines of the parallel band ν7 are just barely seen between the ν11 lines, which are perhaps 30–50 times stronger. Spectroscopic constants for the ν7 band have been obtained from 135 individual lines assigned to the Q- and R-branches of sub-bands with K = 6–21.

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