ABSORPTION SPECTRUM OF THE CCN RADICAL

1965 ◽  
Vol 43 (10) ◽  
pp. 1795-1830 ◽  
Author(s):  
A. J. Merer ◽  
D.N. Travis
Keyword(s):  
Absorption Spectrum ◽  
Transient Absorption ◽  
Flash Photolysis ◽  
Vibrational Energy ◽  
Energy Levels ◽  
Transient Absorption Spectrum ◽  
Molecular Constants ◽  
Angular Momenta ◽  
Show Evidence ◽  
Vibrational Energy Levels

A new transient absorption spectrum, attributed to the CCN free radical, has been discovered in the flash photolysis of diazoacetonitrile, HC(CN)N2; three electronic transitions, between 3 500 Å and 4 700 Å, have been photographed for both CC14N and CC15N. The ground state of the radical is a 2Πr electronic state, and the three excited states observed are A2Δ, B2Σ−, and C2Σ+. The 2Π and 2Δ states show evidence of Renner–Teller interaction between the vibrational and electronic angular momenta, an effect not observed previously for 2Δ states. Theoretical expressions for the vibrational energy levels of linear triatomic molecules in 2Δ electronic states have been derived, in terms of a parameter η associated with the quartic terms in the potential energy. They are compared with the observed pattern in the ν2 = 1 level of the A2Δ state. The principal molecular constants for CC14N (in cm−1) are as follows:[Formula: see text]

The Band System of the CCO Molecule

1971 ◽  
Vol 49 (22) ◽  
pp. 2839-2858 ◽  
Author(s):  
C. Devillers ◽  
D. A. Ramsay
Keyword(s):  
Transient Absorption ◽  
Flash Photolysis ◽  
Energy Levels ◽  
Fermi Resonance ◽  
Lower State ◽  
Linear Molecule ◽  
Transient Absorption Spectrum ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
Sequence Band

The transient absorption spectrum observed previously (Devillers) in the flash photolysis of carbon suboxide has been studied under high resolution in the region 5000 to 9000 Å and assigned to the CCO radical. A rotational analysis of the 000–000 band near 8580 Å shows conclusively that the electronic transition is [Formula: see text]. From molecular orbital considerations the lower state is assigned as [Formula: see text]. Short progressions involving the stretching vibrations (ν1′ = 0–3, ν3′ = 0–1) have been observed. A Fermi resonance has been found involving ν3′ and 2ν2′. Some sequence bands have been assigned; in particular the 010–010 sequence band clearly shows the Renner splittings expected for the Ã3Πi excited state. A band with a different type of rotational structure has been assigned to the forbidden component 010 3Σ(−) – 000 3Σ−. The rotational analysis of this band is in excellent agreement with the theory of Hougen for the rotational energy levels of a linear molecule in the ν2 = 1 level of a 3Π state.The following molecular constants have been obtained:[Formula: see text]

Photochemical Properties of 2-Aryl-3-imino-1-indones

1992 ◽  
Vol 47 (12) ◽  
pp. 1243-1247 ◽  
Author(s):  
I. Timtcheva ◽  
N. Getoff ◽  
P. Nikolov ◽  
R. M. Quint
Keyword(s):  
Absorption Spectrum ◽  
Steady State ◽  
Reaction Mechanisms ◽  
Transient Absorption ◽  
Flash Photolysis ◽  
Uv Light ◽  
Transient Absorption Spectrum ◽  
Light Illumination ◽  
Probable Reaction ◽  
Photochemical Properties

Steady state as well as flash photolysis experiments of 2-aryl-3-imino-1-indones (2-AIID) have been carried out with the aim to learn more about their photochemical properties. It was established that in ethanol these substances exist solely in the keto-enamine-form and are rather photostable under the influence of uv-light. Illumination in dichloroethane, acetonitrile and dioxane is leading to stable photoproducts. A typical transient absorption spectrum of 2-AIID is presented. Probable reaction mechanisms are given.

ROTATIONAL ANALYSIS OF BANDS OF THE HCF MOLECULE

1966 ◽  
Vol 44 (7) ◽  
pp. 1541-1550 ◽  
Author(s):  
A. J. Merer ◽  
D. N. Travis
Keyword(s):  
Transient Absorption ◽  
Flash Photolysis ◽  
Bond Angle ◽  
Large Change ◽  
Transient Absorption Spectrum ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
Ordinary Type ◽  
Type C ◽  
Axis Switching

A new transient absorption spectrum, belonging to the HCF free radical, has been discovered in the flash photolysis of dibromofluoromethane, HCFBr2. The spectrum consists of a single progression of complex bands in the region 4 300–6 000 Å. Rotational analysis of the less severely perturbed bands shows them to be type-C bands of a molecule that is nonlinear in both upper and lower states of the transition, with bond angles of ~ 127° and ~ 102° respectively. Axis-switching effects, due to the large change of bond angle in the transition, cause the appearance of prominent gQ, qQ, and °Q branches, in addition to those obeying the ordinary type-C selection rules.The principal molecular constants of HCF (in cm−1) are:[Formula: see text]

The Visible Absorption Spectrum of Bromine in Solution

1948 ◽  
Vol 1 (4) ◽  
pp. 472 ◽  
Author(s):  
NS Bayliss ◽  
ARH Cole ◽  
BG Green
Keyword(s):  
Absorption Spectrum ◽  
Sulphuric Acid ◽  
Room Temperature ◽  
Vibrational Energy ◽  
Energy Levels ◽  
Visible Absorption Spectrum ◽  
Visible Absorption ◽  
Solvent Molecules ◽  
Vibrational Energy Levels ◽  
Associated Solvents

The visible absorption spectrum of bromine was measured in n-hexane (a normal solvent) and in concentrated sulphuric acid (at room temperature and at -70� C.), phosphoric acid, and ethanol (at -70� C.) as associated solvents. The absorption continuum at 4150 A. in the gas is displaced slightly to the red in n-hexane although other normal solvents may displace it to the violet. The displacement to the violet is greater in associated solvents, ranging from 650 cm.-l in sulphuric acid to over 2000 cm.-1 in ethanol. The displacement in sulphuric acid glass at -70� C, is nearly double the value at 18� C. The displacements in associated solvents are explained in terms of the effect of the semi-rigid cage of solvent molecules surrounding each bromine molecule, and the assumption of " solvates " is unnecessary and undesirable. The spectra in solution are between 40 and 70 per cent. more intense than in the gas, about double the increase that would be predicted by Chako's treatment of the effect of Lorentz-Lorenz forces. The differences in the shape and Emax between solutions in sulphuric acid at 18� C. and at -70� C. are due to the different statistical distribution of bromine molecules between the vibrational energy levels.

scholarly journals Research progress in the effects of terahertz waves on biomacromolecules

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Liu Sun ◽  
Li Zhao ◽  
Rui-Yun Peng
Keyword(s):  
Vibrational Energy ◽  
Rapid Development ◽  
Energy Levels ◽  
Basic Research ◽  
Research Progress ◽  
Biological Macromolecules ◽  
Terahertz Waves ◽  
Terahertz Spectrum ◽  
Biomedical Field ◽  
Vibrational Energy Levels

AbstractWith the rapid development of terahertz technologies, basic research and applications of terahertz waves in biomedicine have attracted increasing attention. The rotation and vibrational energy levels of biomacromolecules fall in the energy range of terahertz waves; thus, terahertz waves might interact with biomacromolecules. Therefore, terahertz waves have been widely applied to explore features of the terahertz spectrum of biomacromolecules. However, the effects of terahertz waves on biomacromolecules are largely unexplored. Although some progress has been reported, there are still numerous technical barriers to clarifying the relation between terahertz waves and biomacromolecules and to realizing the accurate regulation of biological macromolecules by terahertz waves. Therefore, further investigations should be conducted in the future. In this paper, we reviewed terahertz waves and their biomedical research advantages, applications of terahertz waves on biomacromolecules and the effects of terahertz waves on biomacromolecules. These findings will provide novel ideas and methods for the research and application of terahertz waves in the biomedical field.

scholarly journals MARVEL: measured active rotational–vibrational energy levels

2007 ◽  
Vol 245 (2) ◽  
pp. 115-125 ◽  
Author(s):  
Tibor Furtenbacher ◽  
Attila G. Császár ◽  
Jonathan Tennyson
Keyword(s):  
Vibrational Energy ◽  
Energy Levels ◽  
Vibrational Energy Levels

scholarly journals Vibrational band-structures caused by internal rotations of the boron Wankel rotor B11−

RSC Advances ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 3613-3621
Author(s):  
Yonghong Xu ◽  
Huihui Wang ◽  
Yonggang Yang ◽  
Changyong Li ◽  
Liantuan Xiao ◽  
...  
Keyword(s):  
Vibrational Energy ◽  
Energy Levels ◽  
Vibrational Band ◽  
Spectral Broadening ◽  
Band Structures ◽  
Internal Rotations ◽  
Vibrational Energy Levels

The band structures of the vibrational energy levels of B11− lead to corresponding spectral broadening. The vibrational band-structures of planar boron rotors are caused by internal rotations.

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