The vacuum ultraviolet spectrum of the bromine molecule

1969 ◽  
Vol 47 (22) ◽  
pp. 2525-2538 ◽  
Author(s):  
Putcha Venkateswarlu
Keyword(s):  
Absorption Spectrum ◽  
Ionization Potential ◽  
Ground State ◽  
Vacuum Ultraviolet ◽  
Band System ◽  
Rydberg States ◽  
Ultraviolet Spectrum ◽  
Similar Series ◽  
Ionization Limit ◽  
Rydberg Transitions

The absorption spectrum of bromine has been photographed in the first and higher orders of a 10.7-m. concave vacuum grating spectrograph in the region 1700–1170 Å.A number of band systems have been obtained in the region 1510–1170 Å, most of which correspond to Rydberg transitions. In addition, an extensive band system with closely-spaced bands degraded to longer wavelengths has been recorded in the region 1700–1500 Å. Among the Rydberg systems, five series have been found to converge to 85 165 ± 80 cm−1 which represents the ionization potential of the molecule leading to the 2Π3/2g state of the molecular ion. They arise due to transitions from the ground state to [σg2πu4πg32Π3/2g]npσu, [σg2πu4πg32Π3/2g]npπu, [σg2πu4πg32Π3/2g]nfσu, [σg2πu4πg32Π3/2g]nfπu, and [σg2πu4πg32Π3/2g]nfδu configurations where n takes the running values 5, 6, 7, … etc. The first few members of four similar series corresponding to the transitions to the states involving the [σg2πu4πg32Π1/2g] core have been identified and the ionization limit of these series is estimated to be at 88 306 ± 80 cm−1. Two of the remaining band systems have been found to be very likely due to transitions to the Rydberg states with the configurations [σg2πu3πg42Π3/2u]5sσg and [σg2πu3πg42Π1/2u]5sσg, respectively. Three of the observed systems which do not involve Rydberg states appear to have for their upper levels the 1Πu(1u), 3Π(1u), and 3Π(0u+) states arising from the configuration σgπu3πg4σu2.

The Vacuum Ultraviolet Spectrum of ICI

1975 ◽  
Vol 53 (8) ◽  
pp. 812-824 ◽  
Author(s):  
Putcha Venkateswarlu
Keyword(s):  
Absorption Spectrum ◽  
Ionization Potential ◽  
Ground State ◽  
Vacuum Ultraviolet ◽  
Band System ◽  
Ultraviolet Spectrum ◽  
Similar Series ◽  
Iodine Chloride ◽  
Rydberg Transitions ◽  
Concave Grating

The absorption spectrum of iodine chloride has been photographed in the high orders of a 10.7 m concave grating spectrograph in the region 1900–1220 Å. A number of band systems which correspond to Rydberg transitions have been obtained. In addition an extensive band system with closely spaced bands degraded to longer wavelengths has been observed in the region 1660–1580 Å. Among the Rydberg systems, 12 series have been found to converge to 81 362 ± 80 cm−1 which very likely represents the ionization potential of the molecule leading to the 2Π3/2 state of the molecular ion. They are due to transitions from the ground state to states arising from the configurations (σ2π4π32Π3/2)ns σ, (2Π3/2)np σ, (2Π3/2)np π, (2Π3/2)nd σ, (2Π3/2)nd π, (2Π3/2)nd δ, (2Π3/2)nf σ, (2Π3/2)nf π, and (2Π3/2)nf δ where n takes the running values 6, 7, 8, … for the first three configurations, 5, 6, 7, … for the next three configurations, and 4, 5, 6, … for the last three configurations. The first few numbers of 11 similar series corresponding to the transitions to the states involving the (σ2π4π32Π1/2) core have been identified and the ionization of these series is estimated to be at 85 996 ± 80 cm−1.

The 1650-1350 Å absorption spectrum of nitrogen dioxide

1962 ◽  
Vol 267 (1330) ◽  
pp. 395-407 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Nitrogen Dioxide ◽  
Ionization Potential ◽  
Ground State ◽  
Band System ◽  
Anharmonic Constant ◽  
Rydberg Transitions ◽  
First Ionization Potential

An analysis of the 1650-1350 Å band system of nitrogen dioxide has been carried out. A pattern of band spacings and intensities is found that is complex but regular. It is shown that this pattern is qualitatively, and to a large extent quantitatively, just what would be expected for a transition in which the shape of the molecule changes from bent to linear. The transition is a parallel one and the upper state has 2 Σ + u symmetry. The symmetrical stretching frequency is increased from its ground-state value to ca. 1420 cm -1 in the upper state. The upper-state bending frequency is ca. 600 cm -1 . The N — O length is decreased from its groundstate value, probably to 1·1(3) Å. The upper state resembles closely the ground state of NO + 2 . The transition is to be classed as one of the Rydberg transitions leading to the first ionization potential of NO 2 ; and the orbital to which the odd electron is transferred in the transition is (pσ) in type. The anharmonic constant g 22 for the linear upper state is found to be 2·(3) cm -1 . Other Rydberg transitions may well be present in the region, but have not been definitely identified.

Vacuum ultraviolet spectrum of the iodine molecule

1970 ◽  
Vol 48 (9) ◽  
pp. 1055-1079 ◽  
Author(s):  
Putcha Venkateswarlu
Keyword(s):  
Vacuum Ultraviolet ◽  
Rydberg States ◽  
Rydberg Series ◽  
Molecular Ion ◽  
Similar Series ◽  
Common Limit ◽  
The Common ◽  
Ionization Limit ◽  
Rydberg Transitions ◽  
Concave Grating

The absorption spectrum of iodine has been photographed in the higher orders of a 10.7 m concave grating spectrograph in the region 1950–1200 Å. A number of band systems has been obtained, most of which correspond to Rydberg transitions. The limit of the Rydberg series leading to the 2Π3/2g state of the molecular ion has been recorded and the corresponding ionization potential is found to be 75 814 ± 10 cm−1. Five series have been found which terminate at this common limit. They represent transitions from the ground state to [σg2πu4Πg32Π3/2g]np σu Π1u, [σg2πu4πg32Π3/2g]np πu Σ+ (0u+), [σg2πu4πg32Π3/2g]nf σu Π1u, [σg2πu4πg32Π3/2g]nf πu, Σ+(0u+), and [σg2πu4πg32Π3/2g]nf δu Π1u states respectively, where n takes the running values 6, 7, 8, … etc. for the first three series and 4, 5, 6, … etc. for the last two series. The series limit of the bands corresponding to the molecules with ν″ = 1 has been found to be at 75 600 ± 10 cm−1. The first few members of similar series corresponding to transitions to different states involving the common [σg2πu4πg32Π1/2g] core have been identified and the ionization limit of these series is estimated to be at 80 895 ± 50 cm−1. Some of the remaining band systems obtained have been found to be very likely due to transitions to the Rydberg states involving molecular ion cores like [σg2πu 3πg42Π3/2u], [σg2πu3πg42Π1/2u], and [σg2πu4πg2σu2Σu+]. Three of the observed band systems do not appear to involve Rydberg states and their upper levels are very likely the 1Π(1u), 3Π(1u), and 3Π(0u+) states arising from the configuration σgπu3πg4σu2. The positions of these levels are at 64 956, 62 844, and 61 847 cm−1, the corresponding vibrational frequencies being 145, 144, and 109 cm−1 respectively.

The absorption spectrum of Cl2 in the vacuum ultraviolet

1981 ◽  
Vol 59 (6) ◽  
pp. 835-840 ◽  
Author(s):  
A. E. Douglas
Keyword(s):  
Absorption Spectrum ◽  
Vacuum Ultraviolet ◽  
Band System ◽  
Rydberg States ◽  
Ultraviolet Region ◽  
Isotopic Molecule ◽  
Vacuum Ultraviolet Region ◽  
Vibrational Constants ◽  
Made In

The absorption spectrum of Cl2 in the vacuum ultraviolet region has been photographed with sufficient resolution to allow rotational analyses of many bands. The separated isotopic molecule 35Cl2 and cooled absorption cells were used to simplify the spectrum. A band system associated with an ionic state has been observed in the 1330–1450 Å range. Many large perturbations in the system prevent the determination of the usual rotational and vibrational constants. Some progress has been made in the analyses of a few bands associated with Rydberg states.

The electronic spectrum of F2

1976 ◽  
Vol 54 (13) ◽  
pp. 1343-1359 ◽  
Author(s):  
E. A. Colbourn ◽  
M. Dagenais ◽  
A. E. Douglas ◽  
J. W. Raymonda
Keyword(s):  
Absorption Spectrum ◽  
Ground State ◽  
Band System ◽  
Rydberg States ◽  
Rotational Analysis ◽  
Interaction Energies ◽  
Rydberg Series ◽  
Rotational Constants ◽  
Vibrational Levels ◽  
Ionic States

The absorption spectrum of F2 in the 780–1020 Å range has been photographed at sufficient resolution to allow a rotational analysis of many bands. A large number of vibrational levels of three ionic states have been observed and their rotational constants determined. Many perturbations in the rotational structure caused by the interaction between the three states have been investigated and the interaction energies determined. The rotational and vibrational structures of a few Rydberg states have also been analyzed in detail but no Rydberg series have been identified. The difficulties in assigning the observed states are discussed. A 1Σu+ – X1Σg+ emission band system has been observed in the 1100 Å region. An analysis of the bands of this system has allowed us to determine the term values and rotational constants of all the vibrational levels of the ground state with ν ≤ 22. The dissociation energy, D0(F2), is found to be greater than 12 830 and is estimated to be 12 920 ± 50 cm−1.

Rydberg series and autoionization resonances in the Y I absorption spectrum

1973 ◽  
Vol 333 (1592) ◽  
pp. 17-24 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Ionization Potential ◽  
Excited States ◽  
Spectral Range ◽  
Ground State ◽  
Rydberg Series ◽  
A Value ◽  
Doublet Ground State ◽  
Ionization Limit ◽  
First Ionization Potential

The absorption spectrum of yttrium vapour has been photographed in the spectral range 1650 to 2250 À, with a 10 m spectrograph. Series of autoionization resonances, which converge on excited states of the Y + ion have been identified, as combinations with the doublet ground-state of Y I , 5s 2 4d 2 D 3/2 , 5/2 . Although the lines of these series show broadened and often asymmetrical profiles, the lines are sufficiently well defined to fix a value for the first ionization potential of Y I , which differs from the previously accepted value by approximately 2500 cm -1 . In addition, approximately 400 new Y I lines, which involve excited levels below the first ionization limit of Y I , namely 4s 2 1 S o , have been found. The majority of these are unclassifiable at present but, the value for the first ionization-potential being known from the resonances above-mentioned, two series of the character 5s 2 4d 2 D 3/2 , 5/2 -5s 2 nf 2 F o have been identified. In addition to the identifications of series, 152 new lines below the 5s 2 1 S o limit identify 76 new levels of Y I , of odd parity.

The spectrum of Cr I between 179.8 and 200 nm wavelengths, absorption cross sections, and oscillator strengths

1975 ◽  
Vol 342 (1630) ◽  
pp. 431-438 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Ionization Potential ◽  
Cross Section ◽  
Cross Sections ◽  
Ground State ◽  
Absorption Cross Section ◽  
Column Density ◽  
Oscillator Strengths ◽  
Absorption Cross ◽  
Ionization Limit

The absorption spectrum of furnace-heated Cr vapour at wavelengths below 200 nm was recorded photoelectrically and by photography. By use of the hook method, the column density of neutral Cr atoms in the ground state was determined with the aid of the accurately known oscillator strengths of the resonance lines near 427 nm. The absorption cross section of the autoionized lines that dominate the ionization continuum could thus be obtained on an absolute scale. We also measured the wavelengths of many hitherto unreported lines near the ionization limit and derived a new value for the ionization potential, namely 54575.6 ± 0.3 cm -1 . Oscillator strengths for some of these lines are also given.

THE ABSORPTION SPECTRUM OF CF2

1967 ◽  
Vol 45 (7) ◽  
pp. 2355-2374 ◽  
Author(s):  
C. Weldon Mathews
Keyword(s):  
Absorption Spectrum ◽  
Electronic State ◽  
Ground State ◽  
Band System ◽  
Electronic States ◽  
Vibrational Structure ◽  
Rotational Structure ◽  
Transition Moment ◽  
High Dispersion ◽  
Parallel Type

The absorption spectrum of CF2 in the 2 500 Å region has been photographed at high dispersion, and the rotational structure of a number of bands has been analyzed. The analysis of the well-resolved subbands establishes that these are perpendicular- rather than parallel-type bands, as previously assigned. Further analysis shows that the upper and lower electronic states are of 1B1 and 1A1symmetries respectively, corresponding to a transition moment that is perpendicular to the plane of the molecule. In the upper electronic state, r0(CF) = 1.32 Å and [Formula: see text], while in the ground state, r0(CF) = 1.300 Å and [Formula: see text]. An investigation of the vibrational structure of the band system has shown that the vibrational numbering in ν2′ must be increased by one unit from earlier assignments, thus placing the 000–000 band near 2 687 Å (37 220 cm−1). A search between 1 300 and 8 500 Å showed two new band systems near 1 350 and 1 500 Å which have been assigned tentatively to the CF2 molecule.

scholarly journals High Resolution Photoionization Spectrum of HBr Measured With Frequency Tripled Laser Radiation

1987 ◽  
Vol 7 (2-4) ◽  
pp. 129-139 ◽  
Author(s):  
Toshiaki Munakata ◽  
Tadahiko Mizukuki ◽  
Akira Misu ◽  
Motowo Tsukakoshi ◽  
Takahiro Kasuya
Keyword(s):  
Laser Radiation ◽  
High Resolution ◽  
Ultraviolet Radiation ◽  
Ground State ◽  
Vacuum Ultraviolet ◽  
Second Harmonic ◽  
Rydberg Series ◽  
Vacuum Ultraviolet Radiation ◽  
Ionization Limit ◽  
Photoionization Spectrum

The photoionization spectrum of HBr around the first ionization limit was measured at resolution of up to 5 x 10−4 nm. The ionizing vacuum ultraviolet radiation was generated by frequency tripling of the second harmonic output of a dye laser. Three sets of Rydberg series, each converging to the ground state (2Π3/2) of HBr+, were observed on the longer wavelength side of the ionization limit. By extrapolation of the Rydberg series, the ionization potential of HBr was determined to be 11.666 ± 0.001 eV.

Absorption spectrum of the NO molecule. VIII. The heterogeneous (2Σ–2Π) interactions between excited states

1968 ◽  
Vol 46 (8) ◽  
pp. 987-1003 ◽  
Author(s):  
Ch. Jungen ◽  
E. Miescher
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Excited States ◽  
Rydberg State ◽  
Vacuum Ultraviolet ◽  
Principal Quantum Number ◽  
Rydberg States ◽  
Infrared Emission ◽  
Strong Interactions ◽  
Rydberg Series

Heterogeneous perturbations 2E+ ~ 2Π of largely different magnitudes are observed with high resolution in the vacuum-ultraviolet absorption and in the infrared emission spectrum of the NO molecule. The rotational interactions between 2Σ+ Rydberg states and levels of the B2Π non-Rydberg state are shown to be "configurationally forbidden", but produced by the configuration interaction between the non-Rydberg levels and 2Π Rydberg states. The latter together with the 2Σ+ Rydberg states form p complexes. In this way the interactions display the l uncoupling in the complexes; they can be evaluated theoretically and can be analyzed fully. The cases of the strong interactions D2Σ+(v = 3) ~ B2Π(v = 16)and D2Σ+(v = 5) ~ B2Π(v = 21) and of the weaker D2Σ+(v = 1) ~ B2Π(v = 11), all three observed as perturbations in ε bands crossing 3 bands, are discussed in detail. It is further shown that perturbations between γ bands and β bands as well as perturbations between analogous bands of higher principal quantum number are absent, and thus the assignment of the A2Σ+ and E2Σ+ states to the s Rydberg series is confirmed.

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