Isolation of stable intermediates in reactive gas mixtures: Rotational spectrum of H3P...Cl2in a pulsed jet

The rotational spectrum of the 1:1 benzaldehyde-CO2 complex has been investigated by pulsed-jet Fourier transform microwave spectroscopy complemented with quantum chemical calculations. Two isomers, both characterized by one C···O tetrel...

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Thermodynamic properties of reactive gas mixtures

Journal of the Franklin Institute ◽

10.1016/0016-0032(51)90003-8 ◽

1951 ◽

Vol 251 (4) ◽

pp. 437-452 ◽

Cited By ~ 1

Author(s):

Ashley S. Campbell

Keyword(s):

Thermodynamic Properties ◽

Gas Mixtures ◽

Reactive Gas

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Isolation of a Halogen-Bonded Complex Formed between Methane and Chlorine Monofluoride and Characterisation by Rotational Spectroscopy and Ab Initio Calculations

Molecules ◽

10.3390/molecules24234257 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4257 ◽

Cited By ~ 1

Author(s):

Anthony C. Legon ◽

David G. Lister ◽

John H. Holloway ◽

Devendra Mani ◽

Elangannan Arunan

Keyword(s):

Ab Initio Calculations ◽

Ab Initio ◽

Internal Rotation ◽

Halogen Bond ◽

Spectroscopic Constants ◽

Bond Critical Point ◽

Equilibrium Geometry ◽

Rotational Spectrum ◽

Pulsed Jet ◽

Explicitly Correlated

A halogen-bonded complex formed between methane and chlorine monofluoride has been isolated in the gas phase before the reaction between the components and has been characterised through its rotational spectrum, which is of the symmetric-top type but only exhibits K = 0 type transitions at the low effective temperature of the pulsed-jet experiment. Spectroscopic constants for two low-lying states that result from internal rotation of the CH4 subunit were detected for each of the two isotopic varieties H4C···35ClF and H4C···37ClF and were analysed to show that ClF lies on the symmetry axis with Cl located closer than F to the C atom, at the distance r0(C···Cl) ≅ 3.28 Å and with an intermolecular stretching force constant kσ ≅ 4 N m−1. Ab initio calculations at the explicitly correlated level CCSD(T)(F12c)/cc-pVTZ-F12 show that in the equilibrium geometry, the ClF molecule lies along a C3 axis of CH4 and Cl is involved in a halogen bond. The Cl atom points at the nucleophilic region identified on the C3 axis, opposite the unique C–H bond and somewhere near the C atom and the tetrahedron face centre, with re(C···Cl) = 3.191 Å. Atoms-in-molecules (AIM) theory shows a bond critical point between Cl and C, confirming the presence of a halogen bond. The energy that is required to dissociate the complex from the equilibrium conformation into its CH4 and ClF components is only De ≅ 5 kJ mol−1. A likely path for the internal rotation of the CH4 subunit is identified by calculations at the same level of theory, which also provide the variation of the energy of the system as a function of the motion along that path. The barrier to the motion along the path is only ≅ 20 cm−1.

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Nanocrystalline Thin Films for Tunable High Q UHF/VHF Devices

MRS Proceedings ◽

10.1557/proc-603-213 ◽

1999 ◽

Vol 603 ◽

Author(s):

Winston N. Win ◽

Jin-Young Park ◽

Rodger M. Walser

Keyword(s):

Thin Films ◽

Gas Mixtures ◽

Nanocrystalline Films ◽

Frequency Range ◽

Quality Properties ◽

High Q ◽

Sputtered Films ◽

Nanocrystalline Thin Films ◽

Thickness Independent ◽

Reactive Gas

AbstractRecent studies indicate that reactively sputtered FeCrTaN nanocrystalline thin films have many of the properties [large magnetization (4πMs), anisotropy (Han), and resistivity (ρ)] required for application in high Q (>1000), magnetically tunable devices operating in the VHF/UHF (∼50 MHz to 500 MHz) frequency range. These films had thickness (d) of ∼0.1 -µm, but film thickness of ∼1-µm may be required for many devices. Although most previous research has shown that the magnetic properties of sputtered films are significantly deteriorated when d∼1-µm, there are recent reports that those of reactively sputtered nanocrystalline films of similar alloys (FeTaN, CoAl/SiO) are independent of thickness to d≈1-2-µm. Accordingly, this work investigated the possibility of reactively sputtering FeCrTa alloys in O/N gas mixtures to obtain films with device quality properties, that are independent of thickness to 1-2µm. The correlations between their magnetic and electrical properties, and their nano-heterogeneous microstructure, were studied to determine optimum reactive gas mixtures and sputtering parameters. Cross-section TEM studies were conducted to investigate the origins of the thickness independent properties, and the unexpected increases in anisotropy.

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Effect of porous barriers on the molecular compositions of reactive gas mixtures

The Journal of Chemical Physics ◽

10.1063/1.1681744 ◽

1974 ◽

Vol 61 (10) ◽

pp. 4358-4360 ◽

Cited By ~ 7

Author(s):

Pirooz Mohazzabi ◽

Alan W. Searcy

Keyword(s):

Gas Mixtures ◽

Porous Barriers ◽

Reactive Gas

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