48 research outputs found
INTERNUCLEAR POTENTIAL AND EQUILIBRIUM STRUCTURE OF
Author Institution: Laboratories de Physique Mol\'eculaire at Atmosph\'erique, Tour 13. Universit\'e Pierre et Marie Curie et CNRS; Laboratoire de M\'et\'eorologie Dynamique, CNRS, Ecole PolytechniqueThe internuclear potential up to sextic terms and the equilibrium structure of nitrous oxide molecule are reinvestigated using the algebraized contact transformation method previously applied to carbon dioxide. Infrared spectroscopic data for a large number of vibrational levels belonging to six isotopic species of are included in the refinement. The following R.M.S. between calculated and experimental molecular constants are obtained () The equilibrium bond lengths are found to be (A) from which accurate values of equlibrium and ground state rotational constants are calculated for the 12 isotopic species of $N_{2}O.
Stereotypes Against Women Principals in Rural Communities: An Individual or Cultural Issue? A Synthesis into Indigenous Knowledge Systems
Entrenched socio-cultural stereotypes which tend to undermine women’s ability to be leaders and managers cut across the social strata. The experience that informs this article is drawn from an African perspective. Discrimination and prejudice with respect to women’s ability to lead and to manage is universal. Feminist discourse and the bill of human rights are however, beginning to impact positively on these stereotypes. The research was conducted in Limpopo Province. This investigation illuminated the challenges that are faced by women leaders in their schools as well as communities, regardless of the fact that most women are already leading in their households as their partners are based far away from their homes because of work commitments. However there is a general impression that women are not good leaders. Therefore this investigation also probes into the general impressions created about women leadership. A Northern Sotho proverb which most individuals cite in reference to women leadership is: “Tsa etwa ke ya tshadi pele di wela leopeng” which means: “if a leader is a woman, disaster is bound to happen”. Thus a question which one can ask is, does this proverb encourage women discrimination in the cultural settings and work environment?Keywords: Cultural stereotypes, women principals, leaders, rural communities
ABSORPTION SPECTRUM OF NITROUS OXIDE IN THE REGION OF AND
Author Institution: Laboratoire de Spectronomie Mol\'{e}culaire, Universit\'{e} Pierre et Marie Curie; Department of Physics, The Pennsylvania State UniversityWe report the absorption spectrum of natural and isotopicaly enriched samples of observed from 1080 to using the Fourier Transform spectrometer at the University of Paris. Measurements were made at temperatures up to . Of special interest are the -doublets. In several bands it was possible to resolve low-J P-branch -doublets where the cc components had higher frequencies than the dd components. Resolved -doublets could be seen in both the P and R branches in one band
A theoretical study of CO
Semi-empirical atom-atom potential energy calculations based on pairwise
additive interactions are performed and, after applying the Born-Oppenheimer
approximation to separate high frequency vibrational modes from low
frequency orientational and translational modes, the infrared vibrational
spectra of CO2 and N2O monomers trapped in an argon matrix at a
temperature of 5 K are determined. It is shown that only a double
substitutional site in argon can accommodate N2O, whereas CO2 is
trapped in two distinct sites, of single and double substitutional types.
The model shows that splitting of the degenerate ν2 mode occurs for
both molecules in the double site. In the ground electronic state, the
vibrational frequency shifts due to the matrix and the vibrational
transition moments for low-lying levels are determined using the contact
transformation method, as used for gas phase calculations. Calculated energy
levels compare well with observed ones and the theory also predicts some
unobserved levels. Moreover, calculations show no significant changes in the
dipole moments of both CO2 and N2O trapped molecules
LINE INTENSITY MEASUREMENTS IN AND THEIR TREATMENT USING THE EFFECTIVE OPERATOR APPROACH. II. THE 5200 TO REGION
L. Daumont, J. Vander Auwera, J-L. Teffo, V. I. Perevalov and S. A. Tashkun, J. Mol. Spectrosc. 208, 281-291 (2001). A. Camparque, G. Weirauch, S. A. Tashkun, V. I. Perevalov, and J-L. Teffo, J. Mol. Spectrosc. 209, 198-206 (2001).Author Institution: Laboratoire de Chimie Physique Mol\'{e}culaire C. P. 160/09, Universit\'{e} Libre de Bruxelles; Groupe de Spectrom\'{e}trie Mol\'{e}culaire et Atmosph\'{e}rique, ESA CNRS 6089, Universit\'{e} de Reims, Facult\'{e} des Sciences, Moulin de la Housse; Institute of Atmospheric Optics, Russian Academy of Sciences, Siberian Branch; Laboratoire de Physique Mol\'{e}culaire et Applications, CNRS, bo\^{i}te 76, Universit\'e Pierre et Marie CurieThis work continues a series of publications devoted to the application of the effective operators approach to the analysis and prediction of vibration-rotation spectra of linear triatomic molecules. In that frame, the present work aims at describing line intensities of cold and hot bands of in its ground electronic state in the spectral range above . In , vibrational interacting levels group in polyads, identified by the so-called polyad number , as a result of the relation existing between the harmonic frequencies. The absorption spectra of , at room temperature, have been recorded in Brussels over the whole range between 3600 and using a Bruker IFS120HR Fourier transform spectrometer. The measurement and analysis of absolute line intensities in the region between 4300 and , involving bands associated with transitions corresponding to and 9, was done We are now measuring absolute line intensities for cold and hot bands associated with transitions corresponding to and 11, observed in the range from 5200 to . Using wavefunctions previously determined from a global fit of an effective hamiltonian to about 18000 line parameters of a corresponding effective dipole moment are then fitted to these experimental intensities. Results will be presented and discussed
LINE INTENSITIES MEASUREMENTS IN CO AND THEIR TREATMENT USING THE EFFECTIVE OPERATORS APPROACH
{S.A. Tashkun, V.I. Perevalov, J.-L. Teffo, L.S. Rothman, and Vl.G. Tyuterev, J. Quant. Spectrosc. Radiat. Transfer \underline{60{Y. Ding, P. Macko, D. Romanini, V.I. Perevalov, S.A. Tashkun, J.-L. Teffo, S. Hu, and A. Campargue, J. Mol. Spectrosc. \underline{226{S.A. Tashkun, V.I. Perevalov, J-L. Teffo, A.D. Bykov, and N.N. Lavrentieva, J. Quant. Spectrosc. Radiat. Transfer \underline{82Author Institution: Institute of Atmospheric Optics, Russian Academy of Sciences, Siberian Branch, 1 Akademicheskii Avenue, 634055 Tomsk, Russia; Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique, CNRS UMR 7092, case 76, Universite Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05, France; Service de Chimie Quantique et Photophysique C.P. 160/09, Universite Libre de Bruxelles, 50 Avenue F. D. Roosevelt, B--1050 Brussels, BelgiumThis work deals with the modeling of line intensities of cold and hot bands of CO corresponding to transitions (), using the effective operators approach.}, 785--801 (1998); J.-L. Teffo, O.M. Lyulin, V.I. Perevalov, and E.I. Lobodenko, J. Mol. Spectrosc. \underline{187}, 28--41 (1998).} In Brussels, 5 unapodized absorption spectra of CO (98\% purity, mbarm, room temperature) were recorded at a resolution of cm (MOPD cm) using a Bruker IFS120HR. absolute line intensities were measured in 9 bands observed between and cm. In Paris, 2 apodized absorption spectra of an O--enriched CO sample (297.0 K, 8.07(2) and 36.07(4) m, = 1.685(8) torr) containing 0.5\% of CO were recorded at a resolution of 0.0043 cm using a home--made FTS. 90 absolute line intensities were measured for 5 bands observed from 3400 to 3700 cm. A least squares fit of 479 observed line intensities, including those measured in this work and published for the 21102-00001 band,}, 146--160 (2004).} allowed determination of 12 effective dipole moment parameters corresponding to the series of transitions (weighted standard deviation = 0.855, RMS deviation = 4.69\%). The new set of effective dipole moment parameters will soon be used to update the \emph{Carbon Dioxide Spectroscopic Databank} (CDSD--1000).}, 165--196 (2003); http://cdsd.iao.ru, http://cdsd.lpma.jussieu.fr, ftp://ftp.iao.ru/pub/CDSD-1000.} Results will be presented and discussed
INFRARED SPECTROSCOPY AND THE MIPAS (MICHELSON INTERFEROMETER FOR PASSIVE ATMOSPHERIC SOUNDING) EXPERIMENT
Author Institution: Laboratoire de Photophysique Mol\'{e}culaire, C.N.R.S., B\^{a}t. 350, Universit\'{e} Paris-Sud; Laboratoire de Physique Moleculaire et Applications, CNRS, Universit\'{e} P. et M. Curie; California Institute of Technology, Jet Propulsion LaboratoryThe Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) experiment is operating on board the ENVISAT satellite and uses a Fourier-transform spectrometer to acquire for the first time high spectral resolution middle infrared emission limb sounding spectra of the Earth atmosphere from space. The measurement capabilities make it possible to determine every 75 s the vertical profile of several atmospheric trace constituents, during both day and night with an almost full coverage of the globe. In a quasi-operational mode atmospheric vertical profiles of temperature and pressure, as well as of concentrations of , and , are retrieved in the altitude range from 12 to 68 km. The analysis and interpretation of the limb spectra require good knowledge of the molecular parameters of these species as well as of the interfering species. In this talk, after a brief presentation of the MIPAS instrument and its capabilities, we will describe the spectroscopic line parameters database compiled for the MIPAS experiment and we will give some examples of improvements