ABSORPTION SPECTRUM OF THE NO MOLECULE: IV. THE G2Σ−–X2Π SYSTEM

1964 ◽  
Vol 42 (5) ◽  
pp. 848-859 ◽  
Author(s):  
A. Lofthus ◽  
E. Miescher
Keyword(s):  
Absorption Spectrum ◽  
Dissociation Energy ◽  
Band System ◽  
The Other ◽  
High Dispersion ◽  
Electron Configuration ◽  
The Many ◽  
No Absorption ◽  
Overlapping Bands

High-dispersion plates of the NO absorption spectrum have been studied between 1600 and 1390 Å for the three isotopic molecules N14O16, N15O16, and N14O18, and G2Σ−–X2Π bands were sorted out from the many overlapping bands in the spectrum. The well-defined band system satisfies the established isotope relations. In contrast with most of the other known NO band systems G2Σ−–X2Π shows almost no perturbations. Vibrational and rotational analyses gave the following constants for the G2Σ− state of N14O16: Te = 62911.7 cm−1; ωe = 1085.54 cm−1, ωexe = 11.083 cm−1, ωeye = −0.1439 cm−1, Be = 1.2523 cm−1, αe = 0.0204 cm−1, γe = 1.3426 Å. The combination defect observed in the G2Σ−–X2Π bands agrees with the defect found in the A2Σ+–X2Π(γ) bands except in sign, which is opposite. Therefore, the symmetry of the G state is confirmed as 2Σ−. The "pure precession" relation between G2Σ− and X2Π is found to hold for the Λ-type doubling of X2Π. The diffuse structure of the band assigned to ν = 10 indicates that G2Σ− is predissociated by a repulsive 2Σ− state dissociating into 2D(N)+3P(O) atoms at 71660 cm−1. The dissociation energy and electron configuration for G2Σ− are discussed.

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.

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.

scholarly journals The spectrum of rubidium hydride, RbH I. Analysis

1939 ◽  
Vol 173 (952) ◽  
pp. 28-37 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Electronic Transition ◽  
Rotational Constant ◽  
Rotational Structure ◽  
Rotational Analysis ◽  
The Many ◽  
Sodium And Potassium ◽  
Line Type ◽  
Overlapping Bands

The spectra of the diatomic hydrides of lithium, sodium and potassium have been studied both in absorption and in emission by several authors, LiH by Nakamura (1930, 1931) and Crawford and Jorgensen (1935), NaH by Hori (1930, 1931) and Olsson (1935), KH by Almy and Hause (1932) and Hori (1933), and recently Almy and Rassweiler (1938) have published details of the absorption spectrum of caesium hydride. All these hydrides show spectra of the “ many-line” type consisting of numerous overlapping bands with open rotational structure and no obvious heads. A rotational analysis shows that they all have the same type of electronic transition, 1Σ → 1Σ ,and are very strongly degraded towards the red. These spectra are all anomalous in that the frequency, ω´ v , and the rotational constant, B'v,increase at first with increasing initial vibrational quantum numbe v `.

scholarly journals RYDBERG ABSORPTION SERIES OF N2

1962 ◽  
Vol 40 (11) ◽  
pp. 1593-1607 ◽  
Author(s):  
M. Ogawa ◽  
Y. Tanaka
Keyword(s):  
Absorption Spectrum ◽  
Electronic States ◽  
Grazing Incidence ◽  
The Other ◽  
Electronic Transitions ◽  
Electron Configuration ◽  
Rydberg Series ◽  
M 31

The absorption spectrum of N2 in the 600–1000 Å region, particularly the Rydberg series, has been reinvestigated with a grazing incidence spectrograph with a 6.8-meter concave grating.Worley–Jenkins' Rydberg series which converges to the [Formula: see text] state of [Formula: see text] was extended to m = 31. It is suggested that the doublet character of this series is due to the two electronic transitions whose upper states are 1Πu and [Formula: see text] given by the electron configurations:[Formula: see text]and[Formula: see text]respectively.Eight Rydberg series, including Worley's third series, were observed in the region between 710 and 950 Å. These series are divided into two groups, each consisting of four vibration series, ν′ = 0, 1, 2, and 3, with one converging to the A2Πu, 1/2 state and the other to the A2Πu, 3/2 state of [Formula: see text]. The upper electronic states of these two groups are assigned as 1Πu and 3Πu states given by the electron configuration:[Formula: see text]Hopfield's Rydberg series which converges to the [Formula: see text] state of [Formula: see text] was extended to m = 21, and in addition, one vibration series (ν′ = 1) was newly observed. The upper electronic states of the series are assigned as [Formula: see text] states, given by the configuration:[Formula: see text]Another absorption series, which is accompanied closely by the Hopfield emission series, was also observed and the upper electronic states of the series are assigned as [Formula: see text] states, given by the configuration:[Formula: see text]

THE SPECTRUM OF SILICON HYDRIDE

1957 ◽  
Vol 35 (1) ◽  
pp. 71-77 ◽  
Author(s):  
A. E. Douglas
Keyword(s):  
Dissociation Energy ◽  
Band System ◽  
Absorption Lines ◽  
High Dispersion ◽  
Silicon Hydride ◽  
Rotational Constants ◽  
Interstellar Absorption

The 0–0, 1–0, 2–1, and 2–2 bands of the 2Δ–2Π band system of SiH have been photographed under high dispersion and analyzed. The vibrational and rotational constants have been determined and the dissociation energy has been found to be 3.19 ± 0.25 ev. A list of SiH lines which may occur as interstellar absorption lines is given.

The Electronic Spectrum of HF. I. The B1Σ+–X1Σ+ Band System

1973 ◽  
Vol 51 (4) ◽  
pp. 434-445 ◽  
Author(s):  
G. Di Lonardo ◽  
A. E. Douglas
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Emission Spectrum ◽  
Electronic Spectrum ◽  
Dissociation Energy ◽  
Band System ◽  
Vibrational Levels ◽  
Internuclear Distances ◽  
X State ◽  
Potential Curves

The electronic emission and absorption spectrum of HF has been photographed at high resolution with a 10 m grating spectrograph. The emission, which extends from 2670 to 1480 Å, consists entirely of bands of the B1Σ+–X1Σ+ (previously denoted as the V1Σ+–X1Σ+)system. From the analysis of 51 bands of the emission spectrum, constants of the vibrational levels of the X state from ν = 7 and 19 and of the B state from ν = 0 to 10 have been determined. The dissociation energy of HF has been found to be D0(HF) = 47 333 ± 60 cm−1. In the absorption spectrum, 56 bands of the B–X system have been identified. Vibrational levels of the B state between ν = 14 and 26 were found to be well behaved and readily analyzed, but levels between ν = 26 and 73 were found to be highly perturbed. Rydberg–Klein–Rees potential curves have been calculated for the B and X states and it is shown that at large internuclear distances the bonding of the B state is almost entirely ionic.

The absorption spectrum of diatomic phosphorus between 1370 and 600 Å

1975 ◽  
Vol 342 (1628) ◽  
pp. 93-111 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Ionization Potential ◽  
Dissociation Energy ◽  
Ground State ◽  
Molecular Orbitals ◽  
The Other ◽  
Ultraviolet Absorption Spectrum ◽  
Rydberg Series ◽  
Far Ultraviolet ◽  
First Ionization Potential

Nine Rydberg series have been observed in the far ultraviolet absorption spectrum of P 2 . Four of these converge to the.(5σ g ) 2 (2π u ) 3 , 2II u (inv.) state of the ion which is established as being the ground state; four to the low-lying ...(5σ g ) (2π u ) 4 , A 2 Ʃ g + state and one to a newly identified (5σ g ) (2π u )3 2πg, F 2 Ʃ + u state. The first ionization potential is found to be 85 229 ± 15 cm-1 (10.567 ± 0.002eV), which is the limit corresponding to the upper component (2II1/2 ) of the inverted X 2II u state. The other limits are observed at 87 179 + 2cm -1 (A 2 Ʃ + g ) and 125 225 ± 10cm -1 (F 2 Ʃ + u ). The series have been interpreted in terms of molecular orbitals and are found to involve excitation of n sσ g , n dσ g , n dπ g and n dδ g for the X 2 II u core; n pπ u , n fσ u , and n fπ u for the A 2 Ʃ + g core and for the A 2 Ʃ + u core. The evaluation and identification of the series limits enables the relative positions of the states of P + 2 to be established. The dissociation energy of P + 2 is estimated to be 4.98 ± 0.01eV.

AFRICAN WOMEN AND FORBIDDEN GROUNDS: FEMALE SEXUALITY AND SELF-DETERMINATION IN AFRICAN LITERATURE

Imbizo ◽  
2017 ◽  
Vol 7 (1) ◽  
pp. 40-54
Author(s):  
Oyeh O. Otu
Keyword(s):  
Female Sexuality ◽  
Sense Of Self ◽  
African Literature ◽  
The Other ◽  
Self Determination ◽  
African Women ◽  
The Core ◽  
The Many ◽  
The One ◽  
Sexual Repression

This article examines how female conditioning and sexual repression affect the woman’s sense of self, womanhood, identity and her place in society. It argues that the woman’s body is at the core of the many sites of gender struggles/ politics. Accordingly, the woman’s body must be decolonised for her to attain true emancipation. On the one hand, this study identifies the grave consequences of sexual repression, how it robs women of their freedom to choose whom to love or marry, the freedom to seek legal redress against sexual abuse and terror, and how it hinders their quest for self-determination. On the other hand, it underscores the need to give women sexual freedom that must be respected and enforced by law for the overall good of society.

The development of body and organ shape

BMC Zoology ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Ansa E. Cobham ◽  
Christen K. Mirth
Keyword(s):  
Relative Position ◽  
Body Shape ◽  
Single Cells ◽  
The Other ◽  
Geometric Features ◽  
Main Text ◽  
Size Characterization ◽  
Organ Shape ◽  
The Many

Abstract Background Organisms show an incredibly diverse array of body and organ shapes that are both unique to their taxon and important for adapting to their environment. Achieving these specific shapes involves coordinating the many processes that transform single cells into complex organs, and regulating their growth so that they can function within a fully-formed body. Main text Conceptually, body and organ shape can be separated in two categories, although in practice these categories need not be mutually exclusive. Body shape results from the extent to which organs, or parts of organs, grow relative to each other. The patterns of relative organ size are characterized using allometry. Organ shape, on the other hand, is defined as the geometric features of an organ’s component parts excluding its size. Characterization of organ shape is frequently described by the relative position of homologous features, known as landmarks, distributed throughout the organ. These descriptions fall into the domain of geometric morphometrics. Conclusion In this review, we discuss the methods of characterizing body and organ shape, the developmental programs thought to underlie each, highlight when and how the mechanisms regulating body and organ shape might overlap, and provide our perspective on future avenues of research.

scholarly journals Teaching innovations in Asian higher education: perspectives of educators

2018 ◽  
Vol 13 (2) ◽  
pp. 179-190 ◽  
Author(s):  
T.M. Wong
Keyword(s):  
Higher Education ◽  
Design Methodology ◽  
Higher Education Institutions ◽  
The Other ◽  
Asian Countries ◽  
Structured Interviews ◽  
Content Type ◽  
Advanced Technologies ◽  
The Many

Purpose The purpose of this paper is to identify the teaching innovations that have been implemented in higher education institutions in Asia and the perspectives of educators on them. Design/methodology/approach Semi-structured interviews were conducted with 28 educators who were affiliated with 23 higher education institutions in ten Asian countries/regions. The interviews covered information about the teaching innovations of the participants’ institutions, the characteristics of the innovative practices and the participants’ views on them. The relationships between the characteristics of institutions and their teaching innovations were also examined. Findings The results showed that the teaching innovations included two main categories, namely, those which involved the use of advanced technologies and those which did not. The innovations that involved the use of advanced technologies were mainly from larger institutions, while the other category was mainly from smaller ones and had been practised for less than 1.5 years. Differences were also identified between the two categories in terms of the aims and importance of innovations, innovative features, the evaluation of innovations and improvements needed for them. Originality/value The results highlighted that technology is only one of the many aspects of teaching innovations, which is different from the view prevailing in the literature. They also suggested that differences in the scale of institutions (in terms of number of students) possibly influences the kind of teaching innovations adopted.

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