High-resolution FTIR spectroscopy of CHClF2 in a supersonic free jet expansion

AbstractThe structure of synthetic aluminosilicates prepared at pH 6 has been investigated by 29Si and 27Al high-resolution solid-state nuclear magnetic resonance (NMR) spectroscopy. Fourier transform infrared (FTIR) spectroscopy and electron microscopy have also been used to characterize the products. The amount of Si and Al in protoimogolite, disordered allophane and other structures has been measured. There is a fair correlation between the intensity of the 349 cm−1 band in the FTIR spectra and the proportion by weight of protoimogolite Si measured by NMR. It is shown that disordered allophanes have similar structures to those proposed by van Reeuwijk and de Villiers (Soil Sci. Soc. Am. Proc. 32 (1968) 238–240), i.e. octahedral Al surrounding a tetrahedral core. Moreover, it is clear that at high Al:Si ratios (⩾1:1), protoimogolite can compete with disordered allophane precursors for aluminum. The driving forces for formation of protoimogolite rather than allophane appear to be long range Al-Al repulsive forces through oxygen.

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Coriolis interaction between the ν7+ν8 and ν4+ν8 bands of 13C2D4 by high-resolution FTIR spectroscopy

Journal of Molecular Spectroscopy ◽

10.1016/j.jms.2019.03.001 ◽

2019 ◽

Vol 359 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Rabia'tul A'dawiah ◽

T.L. Tan

Keyword(s):

High Resolution ◽

Ftir Spectroscopy ◽

Coriolis Interaction

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High-resolution FTIR spectroscopy of HCFC-31 in the 950−1160 cm−1region: rovibrational analysis and resonances in the ν4, ν9and ν5+ν6bands of CH235ClF

Molecular Physics ◽

10.1080/00268976.2015.1053547 ◽

2015 ◽

Vol 113 (23) ◽

pp. 3683-3690 ◽

Cited By ~ 5

Author(s):

P. Stoppa ◽

A. Baldacci ◽

N. Tasinato ◽

A. Pietropolli Charmet ◽

S. Giorgianni ◽

...

Keyword(s):

High Resolution ◽

Ftir Spectroscopy

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

Canadian Journal of Physics ◽

10.1139/p94-165 ◽

1994 ◽

Vol 72 (11-12) ◽

pp. 1294-1306 ◽

Cited By ~ 13

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.

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