BAND SPECTRUM AND STRUCTURE OF THE CH+ MOLECULE; IDENTIFICATION OF THREE INTERSTELLAR LINES

1942 ◽  
Vol 20a (6) ◽  
pp. 71-82 ◽  
Author(s):  
A. E. Douglas ◽  
G. Herzberg
Keyword(s):  
Ground State ◽  
Band System ◽  
Lower State ◽  
Band Spectrum ◽  
Interstellar Space ◽  
Molecular Constants ◽  
Vibrational Levels ◽  
State Formula ◽  
Heat Of Dissociation ◽  
Π State

In a discharge through helium, to which a small trace of benzene vapour is added, a new band system of the type 1Π – 1Σ is found which is shown to be due to the CH+ molecule. The R(0) lines of the 0–0, 1–0, and 2–0 bands of the new system agree exactly with the hitherto unidentified interstellar lines 4232.58, 3957.72, 3745.33 Å, thus proving that CH+ is present in interstellar space. At the same time this observation of the band system in absorption shows that the lower state 1Σ is the ground state of the CH+ molecule. The new bands are closely analogous to the 1II – 1Σ+ BH bands. The analysis of the bands leads to the following vibrational and rotational constants of CH+ in its ground state: [Formula: see text], Be″ = 14.1767, αe″ = 0.4898 cm.−1. The internuclear distance is re″ = 1.1310∙10−8 cm. (for further molecular constants see Table V). From the vibrational levels of the upper 1Π state the heat of dissociation of CH+ can be obtained within fairly narrow limits: D0(CH+) = 3.61 ± 0.22 e.v. From this value the ionization potential of CH is derived to be I(CH) = 11.13 ± 0.22 e.v. The bearing of this value on recent work on ionization and dissociation of polyatomic molecules by electron impacts is briefly discussed.

The electronic spectrum of the CS+ molecular ion: rotational analysis and perturbation effects in the A2Πi–X2Σ+ transition

1978 ◽  
Vol 56 (5) ◽  
pp. 587-600 ◽  
Author(s):  
D. Gauyacq ◽  
M. Horani
Keyword(s):  
Carbon Disulfide ◽  
Ground State ◽  
Valence Electron ◽  
Band System ◽  
Local Perturbation ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
Molecular Ion ◽  
Vibrational Levels ◽  
The Difference

A new emission spectrum in the red region (6000–8000 Å) has been recorded from a low pressure hot cathode discharge through carbon disulfide. This band system has been assigned to the A2Πi–X2Σ+ transition of the CS+ molecular ion on the basis of the rotational analysis and comparison with other nine valence-electron molecules. Molecular constants have been obtained by direct least squares fits of the line frequencies to the difference of the eigenvalues of standard 2Π and 2Σ+ matrices.A local perturbation in the A2Πi (ν = 5) state has been studied quantitatively. The position of the perturbing vibrational level in the X2Σ+ state has been determined within a few centimetre−1. This study gave a consistent set of molecular constants for the ground state of CS+ and allowed a partial deperturbation treatment of the observed vibrational levels of the excited A2Πi state.Numerous bands are also observed in the 4000 Å region. A discussion is given concerning the possible assignment of bands at 4059 and 4110 Å to the CS+B2Σ+–A2Πi (0,0) transition.

Rotational perturbations in the CN(B2Σ+–X2Σ+) tail band system. III. Molecular constants for the 4Π, 4Σ+, A2Πi, and X2Σ+ states

1984 ◽  
Vol 62 (12) ◽  
pp. 1586-1598 ◽  
Author(s):  
Haruhiko Ito ◽  
Yasushi Ozaki ◽  
Takashi Nagata ◽  
Tamotsu Kondow ◽  
Kozo Kuchitsu
Keyword(s):  
Simulation Analysis ◽  
Band System ◽  
Dissociative Excitation ◽  
Band Spectrum ◽  
Spectral Simulation ◽  
Molecular Constants ◽  
Flowing Afterglow ◽  
Π State

The CN(B2Σ+–X2Σ+) tail band system was observed by using the dissociative excitation reactions of HCN and BrCN with Ar(3P0.2) in an argon flowing afterglow. The following intensity anomalies owing to the B2Σ+ ~ 4Π rotational perturbations were analyzed: (νB, ν11) = (9,x), (11,x + 2), and (18,x + 13), where x is estimated to be 0 or 1. These anomalies, as well as(νB, ν11) = (12,x + 3), (14,x + 6), and (17,x + 11), were analyzed by spectral simulation. The CN(B2Σ+–X2Σ+) 14–14 band spectrum observed by Jenkins was re-analyzed, and the molecular constants for the perturbing 4Π state, the interaction constants, and the crossing schemes for the B2Σ+ ~ 4Π perturbations were determined. The intensity anomalies due to the perturbations by the 4Σ+, A2Πi, and X2Σ+ states were also observed: (νB, νΣ) = (15,p + 6), where p is estimated to be 8 ± 1, (νB, νA) = (11, 26) and (17, 34), and (νB, νX) = (11, 28). The molecular constants for the perturbing levels were estimated by a simulation analysis.

Spectrum of the CN molecule. I. Absorption in the vacuum ultraviolet

1970 ◽  
Vol 48 (10) ◽  
pp. 1192-1199 ◽  
Author(s):  
Barry L. Lutz
Keyword(s):  
Vacuum Ultraviolet ◽  
Band System ◽  
Vibrational Analysis ◽  
Electronic States ◽  
Ultraviolet Absorption Spectrum ◽  
Molecular Constants ◽  
Weak Band ◽  
Vibrational Levels ◽  
First Time ◽  
Π State

The vacuum ultraviolet absorption spectrum of CN is observed for the first time revealing a weak band system between 1490 and 1820 Å. Rotational and vibrational analysis shows the upper state to be the known E2Σ+ state. Four new vibrational levels are reported, resulting in the following molecular constants for the E state (cm−1):[Formula: see text]The strength of the absorption and its significance in astrophysics is discussed. The dissociation limits and the electron configurations of all known electronic states of CN are also discussed, and a tentative assignment of a previously unassigned 2Π state is proposed.

STRUCTURE OF THE BAND SPECTRUM OF CuCl MOLECULE: II. ROTATIONAL STRUCTURE OF THE F–X BAND SYSTEM OF Cu65Cl35

1962 ◽  
Vol 40 (4) ◽  
pp. 412-422 ◽  
Author(s):  
P. Ramakoteswara Rao ◽  
R. K. Asundi ◽  
J. K. Brody
Keyword(s):  
High Resolution ◽  
Electronic Transition ◽  
Band System ◽  
Rotational Structure ◽  
Band Spectrum ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
X Band ◽  
Π State

The F–X band system of Cu65Cl35 extending from 3700 to 4200 Å has been photographed in emission under high resolution. Rotational analysis of the (3,0), (2,0), (1,0), (0,0), (0,1), and (0,2) bands of the system has been made. The electronic transition involved is found to be 1Π–1Σ. The Λ-type doubling in the 1Π state is negligible. The principal molecular constants obtained are as follows (cm−1 units)[Formula: see text]

The A–X system of the CuCl molecule

1981 ◽  
Vol 59 (2) ◽  
pp. 289-297 ◽  
Author(s):  
G. P. Mishra ◽  
S. B. Rai ◽  
K. N. Upadhya
Keyword(s):  
High Resolution ◽  
Ground State ◽  
Electronic Transition ◽  
Band System ◽  
Rotational Structure ◽  
Molecular Constants ◽  
X Band ◽  
Standard Deviations ◽  
Concave Grating ◽  
Π State

The A–X band system of CuCl has been photographed in emission under high resolution in the 2nd order of a 10.6 m concave grating spectrograph. Rotational structure in four bands, viz. (1,0), (0,0), (0,1), and (1,2) has been analysed. The present analysis confirms that in the A–X system the electronic transition involved is 1Π–1Σ where 1Σ is the ground state of the molecule. The Λ-type doubling in the 1Π state is found to be appreciable. The molecular constants for the excited A state of 63Cu35Cl are (with standard deviations in parentheses): Be = 0.168432(7) cm−1; αe = 0.001067(7); De = 0.1134(11) × 10−6; q = 0.000871(9); qD = 0.85(18) × 10−8; ν10 = 19 500.271(8); ν00 = 18 999.104(7); ν01 = 18 579.735(10); and ν12 = 18 574.745(11).

ROTATIONAL ANALYSIS OF THE β BANDS OF PHOSPHORUS MONOXIDE

1959 ◽  
Vol 37 (2) ◽  
pp. 136-143 ◽  
Author(s):  
Nand Lal Singh
Keyword(s):  
Ground State ◽  
Band System ◽  
Electronic States ◽  
Rotational Analysis ◽  
Rotational Constants ◽  
Fine Structures ◽  
Π State

The fine structures of three of the β bands of PO which occur near 3200 Å have been analyzed. The analysis shows that the upper state of this band system is a 2Σ and not a 2Π state as previously believed. The rotational constants of both electronic states have been determined and it is found that the ground state constants, previously determined from the γ bands, are incorrect.

Rotational Analysis of the lΠ–XlΣ+ System of C80Se

1974 ◽  
Vol 52 (9) ◽  
pp. 813-820 ◽  
Author(s):  
René Stringat ◽  
Jean-Paul Bacci ◽  
Marie-Hélène Pischedda
Keyword(s):  
Emission Spectrum ◽  
Ground State ◽  
High Frequency ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
High Frequency Discharge ◽  
Perturbed State ◽  
Simple Evaluation ◽  
Π State

The strongly perturbed 1Π–X1Σ+ system of C80Se has been observed in the emission spectrum of a high frequency discharge through selenium and carbon traces in a neon atmosphere. The analysis of five bands yields, for the molecular constants of the ground state, the values Be″ = 0.5750 cm−1, [Formula: see text], αe″ = 0.00379 cm−1, re″ = 1.676 Å, ΔG″(1/2) = 1025.64 cm−1, and ΔG″(3/2) = 1015.92 cm−1. The numerous perturbations in the 1Π state prohibit the simple evaluation of the constants of the perturbed state and of the perturbing ones.

THE LYMAN BANDS OF MOLECULAR HYDROGEN

1959 ◽  
Vol 37 (5) ◽  
pp. 636-659 ◽  
Author(s):  
G. Herzberg ◽  
L. L. Howe
Keyword(s):  
High Resolution ◽  
Vibrational Level ◽  
Ground State ◽  
Molecular Hydrogen ◽  
Equilibrium Constants ◽  
Dissociation Limit ◽  
Vibrational Levels ◽  
State Formula ◽  
Single Formula ◽  
Vibrational Constants

The Lyman bands of H2 have been investigated under high resolution with a view to improving the rotational and vibrational constants of H2 in its ground state. Precise Bv and ΔG values have been obtained for all vibrational levels of the ground state. One or two of the highest rotational levels of the last vibrational level (v = 14) lie above the dissociation limit. Both the [Formula: see text] and ΔG″ curves have a point of inflection at about v″ = 3. This makes it difficult to represent the whole course of each of these curves by a single formula and therefore makes the resulting equilibrium constants somewhat uncertain. This uncertainty is not very great for the rotational constants for which we find[Formula: see text]but is considerable for the vibrational constants ωe and ωexe for which three-, four-, five-, and six-term formulae give results diverging by ± 1 cm−1. The rotational and vibrational constants for the upper state [Formula: see text] of the Lyman bands are also determined. An appreciable correction to the position of the upper state is found.

A NEW BAND SYSTEM OF THE P2 MOLECULE ANALOGOUS TO THE LYMAN–BIRGE–HOPFIELD BANDS OF N2

1958 ◽  
Vol 36 (5) ◽  
pp. 565-570 ◽  
Author(s):  
A. E. Douglas ◽  
K. Suryanarayana Rao
Keyword(s):  
Excited States ◽  
Ground State ◽  
Singlet State ◽  
Band System ◽  
Excited Singlet State ◽  
Lower State ◽  
High Dispersion ◽  
Electron Configuration ◽  
Excited Singlet ◽  
New System

Five bands of a new band system of P2 have been photographed at high dispersion and analyzed. The upper state of the system is a 1П0 state and lies lower than any previously known excited singlet state. The lower state of the new system is the ground state of P2 and the analysis of the new bands has given improved constants for this state. The new system appears to be the analogue of the Lyman–Birge–Hopfield bands of N2. The electron configuration of the low excited states of P2 and of related molecules is discussed.

The Emission Spectrum of PtO between 3800 and 4500 Å

1975 ◽  
Vol 53 (19) ◽  
pp. 1991-1999 ◽  
Author(s):  
Rosemary Scullman ◽  
Ulf Sassenberg ◽  
Christer Nilsson
Keyword(s):  
Emission Spectrum ◽  
Ground State ◽  
Lower State ◽  
Vibrational Levels ◽  
New System

A new system belonging to the emission spectrum of PtO has been found in the region of 3800–4500 Å. This system has the earlier known X1Σ ground state as the lower state and a hitherto unknown 1Σ state, here designated the D1Σ state, as the upper state. The four lowest vibrational levels of the D1Σ state were rotationally analyzed. Of these levels, the [Formula: see text] level seems to be unperturbed although the v′ = 1, 2, and 3 levels are strongly perturbed.

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