High-resolution visible spectrum for the A3Π(l)–X1Σ+ system of IBr

1994 ◽  
Vol 72 (11-12) ◽  
pp. 1265-1272 ◽  
Author(s):  
Dominique R. T. Appadoo ◽  
Peter F. Bernath ◽  
Robert J. Le Roy
Keyword(s):  
High Resolution ◽  
Mechanical Behaviour ◽  
Laser Excitation ◽  
Visible Spectrum ◽  
Molecular Constants ◽  
Excitation Spectra ◽  
The Core ◽  
Global Fit ◽  
X State ◽  
Infrared Data

New high-resolution absorption and laser excitation spectra of the A3Π(1)–X1Σ+ system of IBr, consisting of approximately 4000 lines of over 40 bands spanning the vibrational range ν′ = 6–29 and ν″ = 1–4 for each of the two isotopomers, have been recorded and analyzed. Combined with previous microwave and infrared data and fluorescence progressions into the X state, and with new data obtained from laser excitation of the lowest levels of the A state, they formed the core of a global fit to mass-reduced Dunham expansions that yields new molecular constants for the A and X states of I79Br and I81Br. Inability to fully account for all data within the experimental uncertainties points to the existence of substantial perturbations or "non-mechanical" behaviour for A-state levels ν′ > 24.

Spectroscopy of metastable species in a free-jet expansion: the β ← A transition in IBr

1994 ◽  
Vol 72 (11-12) ◽  
pp. 1294-1306 ◽  
Author(s):  
Jason O. Clevenger ◽  
Quentin P. Ray ◽  
Joel Tellinghuisen ◽  
Xiaonan Zheng ◽  
Michael C. Heaven
Keyword(s):  
High Resolution ◽  
Laser Irradiation ◽  
Laser Excitation ◽  
Excitation Spectra ◽  
Detailed Characterization ◽  
Free Jet ◽  
X State ◽  
Π State ◽  
Existing Data

The A 1(3Π) state of IBr is observed in a free-jet expansion of IBr in Ar, following photolysis with ArF laser irradiation. Laser excitation spectra are obtained for the β 1(3P2) ← A transition in medium (0.5 cm−1) and high (0.08 cm−1) resolution. Sixteen ν′–ν″ bands recorded in high resolution are rotationally analyzed, providing the first detailed characterization of the lowest three νlevels in the A state. An additional ~50 bandheads in the ν″ = 0 and 1 progressions are recorded for both I79Br and I81Br. The new data, which sample ν′ levels in the range 31–71, are combined with existing information for low ν in the β state to provide improved constants for the β state. These results are merged with least-squares parameters from a detailed reanalysis of existing data for the A and X(1Σ+) states to yield spectroscopic parameters valid for ν = 0–20 in the X state and ν = 0–26 in the A state. Among these results are the first precise estimates of the equilibrium parameters in the A state: Te = 12 369.68 (14) cm−1, ωe = 134.22 (13) cm−1, Be = 0.042 40 (5) cm−1, Re = 2.8583 (16) Å.

High-resolution laser-excitation spectrum of the A2Π ← X2Σ system of TiN: rotational analysis of the 0–0, 1–1, and 2–2 bands

1985 ◽  
Vol 63 (7) ◽  
pp. 997-1004 ◽  
Author(s):  
K. Brabaharan ◽  
J. A. Coxon ◽  
A. Brian Yamashita
Keyword(s):  
High Resolution ◽  
Least Squares ◽  
Excitation Spectrum ◽  
Laser Excitation ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
Individual Bands ◽  
Measured Line ◽  
Line Positions ◽  
Π State

The 0–0, 1–1, and 2–2 bands of the A2Π ← X2Σ system of TiN have been recorded using the technique of laser-excitation spectroscopy. Molecular constants have been obtained from direct least squares fits of the measured line positions of individual bands. The fitted constants confirm and extend previous determinations; for the A2Π state, some of the constants show unusually large variations with ν, in accord with the already known perturbation of this state in the ν = 0 level.

High Resolution Spectroscopy of HCN Isotopomers: H13CN, HC15N, and H13C15N in the Ground and First Excited Bending Vibrational State

2004 ◽  
Vol 59 (11) ◽  
pp. 861-874 ◽  
Author(s):  
U. Fuchs ◽  
S. Brünken ◽  
G.W. Fuchs ◽  
S. Thorwirth ◽  
V. Ahrens ◽  
...  
Keyword(s):  
High Resolution ◽  
Vibrational State ◽  
High Resolution Spectroscopy ◽  
Molecular Constants ◽  
Data Set ◽  
Quantum Numbers ◽  
Terahertz Applications ◽  
Global Fit ◽  
Mode A ◽  
Wave Spectrometer

The eleven energetically lowest pure rotational transitions, J ←J−1 (J =1,2, . . . ,11), of H13CN, H13C15N, and HC15N in the ground and first excited bending state were measured. By operating the Cologne Tetrahertz Wave Spectrometer up to 1 THz in the sub-Doppler mode, a transition frequency accuracy of a few kHz is achieved. These measurements were carried out at frequencies between 80 - 950 GHz. In addition, some transitions of the three isotopomers with rotational quantum numbers J = 20,21,22,23 have been measured in Doppler-limited resolution near 2 THz, using the frequency stabilized Cologne Sideband Spectrometer for Terahertz Applications (COSSTA). Furthermore, direct l-type transitions of H13CN in the first excited bending state with J up to 35 have been measured. These new data are of particular importance, since we discovered highly excited circumstellar H12CN recently. A global fit of the newly enlarged data set together with existing carefully screened ro-vibrational data yields molecular constants which are highly reliable and of great importance both for astrophysical observations and laboratory applications

Laser spectroscopy of the A3Φi-X3Φi and B3Φ4-X3Φ4 transitions of iridium monofluoride (IrF) This article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.

2009 ◽  
Vol 87 (5) ◽  
pp. 557-565 ◽  
Author(s):  
A. G. Adam ◽  
A. D. Granger ◽  
L. E. Downie ◽  
D. W. Tokaryk ◽  
C. Linton
Keyword(s):  
High Resolution ◽  
Fluorescence Spectra ◽  
Rotational Analysis ◽  
Special Issue ◽  
Molecular Constants ◽  
High Resolution Data ◽  
Complete Set ◽  
Global Fit ◽  
The University ◽  
Resolution Data

Laser-induced fluorescence spectra of iridium monofluoride (IrF) have been obtained at both low and high resolution. Two transitions have been observed; based on the rotational analysis of the high-resolution spectra, they have been assigned as A3Φi-X3Φi and B3Φi-X3Φi. For the X (ground) and B states, only the lowest Ω = 4 components have been observed, while for the A state, the two lowest components, Ω = 4 and 3, were detected. A global fit to all of the high-resolution data (six bands of A-X and five of B-X) yielded a complete set of molecular constants for all three states of both 191IrF and 193IrF. The v = 3 level of the A3Φ4 state was found to be heavily perturbed and many extra lines belonging to the perturbing state were observed for each isotopologue. A deperturbation analysis showed that the perturber is an Ω = 5 state, and molecular parameters for this state were obtained.

Rotational analysis of the laser excitation spectra of the bromoacetylene and deuterobromoacetylene cations

1984 ◽  
Vol 62 (12) ◽  
pp. 1437-1451 ◽  
Author(s):  
Michael A. King ◽  
John P. Maier ◽  
Liubomir Misev ◽  
Martin Ochsner
Keyword(s):  
Electronic Structure ◽  
High Resolution ◽  
Laser Excitation ◽  
Neutral Molecule ◽  
Rotational Analysis ◽  
Excitation Spectra

High-resolution laser excitation spectra of the [Formula: see text] bands of the bromo- and deuterobromoacetylene cations have been recorded and rotationally analyzed. The new data are compared with those for the neutral molecule and discussed in terms of electronic structure.

High resolution studies of the system of 13C-formaldehyde

1979 ◽  
Vol 57 (10) ◽  
pp. 1676-1680 ◽  
Author(s):  
F. W. Birss ◽  
R. M. Gordon ◽  
D. A. Ramsay ◽  
S. M. Till
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Type B ◽  
Molecular Constants ◽  
Text Type ◽  
Type C

The absorption spectrum of H213CO has been photographed in the region 3600 to 3000 Å under high resolution. Rotational analyses have been carried out for four bands, viz., [Formula: see text], [Formula: see text], [Formula: see text] (Type B), and [Formula: see text] (Type C), and molecular constants are given. Several perturbations have been found and possible mechanisms discussed.

Reconstruction of the last three millennia South American Monsoon variability over the Amazon basin using speleothem isotope records 

2021 ◽  
Author(s):  
Marcela Eduarda Della Libera de Godoy ◽  
Valdir F. Novello ◽  
Francisco William Cruz
Keyword(s):  
High Resolution ◽  
Amazon Basin ◽  
Rainfall Variability ◽  
Isotope Analysis ◽  
Core Region ◽  
South American ◽  
The South ◽  
Continuous Increase ◽  
South American Monsoon ◽  
The Core

<p>South American Monsoon System (SAMS) and its main feature, the South American Convergence Zone (SACZ) are responsible for the major distribution of moisture in South America. The current work presents a novel high-resolution oxygen isotope record (δ<sup>18</sup>O) based on speleothems from southwest Amazon basin (Brazil), right at SAMS' core region and SACZ onset, where there is still a gap of high resolution paleoclimate records. The novel δ<sup>18</sup>O record presents an average of 3 year-resolution, composed by 1344 stable isotope analysis performed in two speleothems with a well-resolved chronology (37 U/Th ages) with average errors <1%. This work aims to describe the rainfall variability of the core region of the South American monsoon for the last 3k years and to take a broader look at precipitation patterns over Amazon basin. The Rondônia δ18O record shows three main stages throughout this time period. The first is from -1000 to ~400 CE, where it’s in accordance with most of other paleorecords from the Amazon basin. the second segment  is from ~400 to 1200 CE, when there is a continuous increase in the δ18O record until it reaches its highest values around 850 CE during the MCA (800-1200 CE), which is in accordance with western Amazon records, whilst the record in eastern Amazon presents an opposite trend. Thus, a precipitation dipole over Amazon emerges from ~400 CE onwards, majorly triggered by anomalous climate changes such as MCA, where western (eastern) Amazon is drier (wetter). During LIA (1450-1800 CE), on the other hand, Rondônia record presents its lowest values, also agreeing with western records and with records under the influence of SACZ whilst on eastern Amazon a drier period is established. Therefore, with this novel paleoclimate record located at the core region of SAMS, it's possible to evidence the dynamics of the precipitation dipole over the Amazon region, as well as understand the SACZ intensity variations.</p>

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