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1.
J Chem Phys ; 137(8): 084303, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22938229

RESUMO

The energies of the J = 2 ortho levels of the v = 0 to 6 Rydberg np singlet series of molecular hydrogen with absolute intensities of the R(1) and P(3) absorption lines were measured by a high-resolution synchrotron radiation experiment and calculated through a full ab initio multi-channel quantum defect approach.

2.
J Chem Phys ; 136(13): 134301, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22482546

RESUMO

The energies and the widths of the J = 1 para levels of the v = 0 to 6 Rydberg np singlet series of molecular hydrogen with absolute intensities of the R(0) and P(2) absorption lines were measured by a high - resolution synchrotron radiation experiment and calculated through a full ab initio multichannel quantum defect theory approach. On the basis of the agreement between theory and experiment, 31 levels were either reassigned or assigned for the first time.

3.
J Chem Phys ; 135(14): 144302, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22010713

RESUMO

The energies, widths and absolute intensities of the P(1) v'' = 0, J'' = 1 absorption transitions of H(2) have been measured in the spectral range of 81-75 nm using monochromatized synchrotron radiation. This work completes and extends previous observations, in particular those of Herzberg and Jungen [J. Mol. Spectrosc. 41, 425 (1972)]. Ab initio multichannel quantum defect theory (MQDT) is used to corroborate the spectral analysis of the experimental data. Line intensities and decay widths are also calculated using MQDT.

4.
J Chem Phys ; 133(14): 144317, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20950010

RESUMO

The 3pπD (1)Π(u) state of the H(2) molecule was reinvestigated with different techniques at two synchrotron installations. The Fourier transform spectrometer in the vacuum ultraviolet wavelength range of the DESIRS beamline at the SOLEIL synchrotron was used for recording absorption spectra of the D (1)Π(u) state at high resolution and high absolute accuracy, limited only by the Doppler contribution at 100 K. From these measurements, line positions were extracted, in particular, for the narrow resonances involving (1)Π(u) (-) states, with an accuracy estimated at 0.06 cm(-1). The new data also closely match multichannel quantum defect calculations performed for the Π(-) components observed via the narrow Q-lines. The Λ-doubling in the D (1)Π(u) state was determined up to v=17. The 10 m normal incidence scanning monochromator at the beamline U125/2 of the BESSY II synchrotron, combined with a home-built target chamber and equipped with a variety of detectors, was used to unravel information on ionization, dissociation, and intramolecular fluorescence decay for the D (1)Π(u) vibrational series. The combined results yield accurate information on the characteristic Beutler-Fano profiles associated with the strongly predissociated Π(u) (+) parity components of the D (1)Π(u) levels. Values for the parameters describing the predissociation width as well as the Fano-q line shape parameters for the J=1 and J=2 rotational states were determined for the sequence of vibrational quantum numbers up to v=17.

5.
Phys Rev Lett ; 104(18): 183002, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20482170

RESUMO

The absolute cross sections for the competing decay channels fluorescence, dissociation, and ionization of photoexcited long-lived superexcited H(2) molecular levels have been measured from the ionization threshold of H(2) up to the H(1s)+H(n=3) dissociation limit. The total and partial natural widths of these levels have been determined. Good agreement is found with first principles calculations carried out by multichannel quantum defect theory. The calculations reproduce the balance between the competing decay processes as well as its substantial level-to-level evolution.

6.
Ned Tijdschr Geneeskd ; 150(32): 1753-5, 2006 Aug 12.
Artigo em Holandês | MEDLINE | ID: mdl-16948232

RESUMO

A 22-year-old woman went through a period with a labile mood that first turned into psychotic hyperactivity and was then followed by hyperthermia and exhaustion. This was accompanied by diminished consciousness, sinus arrhythmia and respiratory insufficiency. With a working diagnosis of 'lethal catatonia' she was treated by electroshock and later also with the antipsychotic agent quetiapine. After a few electroshock treatments her vital functions improved and ultimately, the patient recovered. Lethal catatonia is characterised by acute excitation, catalepsy, autonomic instability and fever, which can lead to death. The syndrome often starts with mood instability, which turns into hyperactivity accompanied by hyperthermia and exhaustion. The creatine kinase, blood-sedimentation rate and leukocyte count are often raised. Lethal catatonia must be distinguished from the neuroleptic malignant syndrome, serotonin syndrome and encephalitis. The pathophysiology is unclear, but most reports suggest a hypodopaminergic state. The syndrome is associated with affective disorders and schizophrenia. Early recognition is made difficult by the low frequency of appearance, diversity in nomenclature, and strong resemblance to other syndromes.


Assuntos
Catatonia/diagnóstico , Catatonia/terapia , Eletroconvulsoterapia , Adulto , Antipsicóticos/uso terapêutico , Diagnóstico Diferencial , Dibenzotiazepinas/uso terapêutico , Dopamina/sangue , Feminino , Humanos , Fumarato de Quetiapina , Resultado do Tratamento
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