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1.
Phys Chem Chem Phys ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967141

RESUMEN

Despite the importance of MgO+ for understanding the electronic structure and chemical bonds in alkaline-earth metal oxides and its potential astrophysical relevance, hardly any spectroscopic information is available on this molecular cation. We report on a high-resolution photoelectron spectroscopic study of MgO using a resonant (1 + 1') two-photon excitation scheme in combination with PFI-ZEKE photoelectron spectroscopy. By carrying out the resonant excitation via selected rotational levels of several intermediate states of different electronic configurations, total electronic spins, and internuclear distances, a broad range of vibrational levels of the X+ 2ΠΩ (Ω = 3/2, 1/2) ground and A+ 2Σ+ first excited states of MgO+ were observed for the first time. The new data provide a full characterisation of the rovibronic level structure of MgO+ up to 2 eV (16 000 cm-1) of internal energy. A full set of vibrational, rotational and spin-orbit-coupling molecular constants were extracted for these two electronic states. The adiabatic ionisation energy and the singlet-triplet interval of 24Mg16O were determined to be 64 577.65(20) cm-1 and 2492.4(3) cm-1, respectively.

2.
J Phys Chem A ; 128(16): 3149-3157, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38619915

RESUMEN

We report on the characterization of the X+ 2Σ+ ground and the A+ 2ΠΩ (Ω = 1/2, 3/2) and B+ 2Σ+ electronically excited states of MgXe+. Rotationally cold MgXe in the a 3Π0(v″ = 0) metastable electronic state was generated in a laser-ablation supersonic-beam source. Following single-photon excitation from the metastable state, the vibrational structure of the X+ state of MgXe+ was measured by pulsed-field-ionization zero-kinetic-energy photoelectron spectroscopy, and the adiabatic ionization energy of the X+ ← a ionizing transition was determined to be EI/(hc) = 37,468.3(6) cm-1. Spectra of the A+ ← X+ and B+ ← X+ transitions were recorded by using the method of isolated-core Rydberg-dissociation spectroscopy. The observation of the Mg+(3p) 2P1/2 + Xe 1S0 dissociation limit enabled the determination of the dissociation energies of the X+ [D0(X+) = 2970(7) cm-1] and A+ states [D0(A1/2+) = 9781(7) cm-1 and D0(A3/2+) = 9603(7) cm-1]. We compare these results with those of earlier experimental studies and ab initio quantum-chemical calculations.

3.
Int J Impot Res ; 9(3): 155-61, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9315493

RESUMEN

This double-blind, placebo-controlled clinical trial of yohimbine hydrochloride included 86 patients with erectile dysfunction and without clearly detectable organic or psychologic causes. The patient group fulfilled all entry criteria; 85 of these could be considered for the Safety-respectively 83 for the Intention-to-treat (ITT)-analysis. Yohimbine was administered orally in a dosage of 30 mg a day (two 5 mg tablets three times daily) for eight weeks. Patients were seen for follow-up after four weeks' treatment, and for a final visit after eight weeks. Efficacy evaluation was based on both subjective and objective criteria. Subjective criteria included improvement in sexual desire, sexual satisfaction, frequency of sexual contacts, and quality of erection (penile rigidity) during sexual contact/intercourse. Objective criteria of outcome were based on improvement in penile rigidity determined by use of polysomnography in the sleep laboratory. Overall Yohimbine was found significantly more effective than placebo in terms of response rate: 71 vs 45%. Yohimbine was well-tolerated: Only 7% of patients rated tolerability fair or poor, and most adverse experiences were mild. There was no serious adverse event.


Asunto(s)
Antagonistas Adrenérgicos alfa/uso terapéutico , Disfunción Eréctil/tratamiento farmacológico , Yohimbina/uso terapéutico , Adulto , Anciano , Coito , Método Doble Ciego , Disfunción Eréctil/fisiopatología , Disfunción Eréctil/psicología , Humanos , Masculino , Persona de Mediana Edad , Erección Peniana , Placebos , Sexualidad , Resultado del Tratamiento , Yohimbina/efectos adversos
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