Perfluorination of Aromatic Compounds Reinforce Their van der Waals Interactions with Rare Gases: The Rotational Spectrum of Pentafluoropyridine-Ne

The rotational spectrum of the pentafluoropyridine-Ne complex, generated in a supersonic jet, has been investigated using chirped-pulse microwave Fourier transform spectroscopy in the 2–8 GHz range. The spectra of the 20Ne and 22Ne species have been observed, and the rotational constants have been used to determine the structure of the complex. This structure, and those of the previously experimentally studied complexes benzene-Ne and pyridine-Ne, are an excellent benchmark for the theoretical calculations on these adducts. These complexes and hexafluorobenzene-Ne have been investigated at the CCSD/6-311++G(2d,p) level. The calculations reproduce the experimental structures well and show how the van der Waals complexes are stronger for the perfluorinated compound.

Study of Ne:He Plasma of a Periodically Pulsed Discharge for Optically Pumped Rare Gas Laser

Optically pumped rare gas lasers (OPRGL) suggested recently as a chemically inert analog of diode-pumped alkali lasers are under extensive study at present. OPRGLs employ metastable atoms of heavier rare gases (Rg*) in He bath produced in discharge plasma. Ar* OPRGL is the most popular system at present, due to presence of a narrow band diode pump and abundance of Ar. However, Ne* OPRGL is interesting due to its visible lasing wavelength at 703.2 nm nm and presence of channels of energy transfer in Ne-He plasma that facilitate Ne* production. We present the first results of experiments with Ne* OPRGL that include Ne* number density in its active medium, and lasing experiments to determine pumping threshold for s5 → p9 transition in a transverse pumping configuration using a narrow band pulsed dye laser as a pump.

Second virial coefficient for the exponent--spline-Morse-spline-van der Waals potential and its application

An analytical expression for the second virial coefficient based on an exponent-spline-Morse-spline-van der Waals (ESMSV) potential is presented here for use in defining the thermodynamic properties of rare gases. Our method is established based on a series expansion of the exponential function, Meijer function, gamma function, binomial function, and hypergeometric function. Numerical approaches have commonly been used for the evaluation of the second virial coefficient with the ESMSV potential in the literature. The general formula obtained here can be applied to estimate the thermal properties of rare gases. Our results for the second virial coefficient based on the ESMSV potential of He-He, He-Ne, He-Ar, and He-Xe rare gases are compared with numerical calculations and experimental data, and it is shown that our analytical expression can be successfully used for other gases.

Seismotectonics of the High Mountain Part of the Eastern Caucasus and the Prospects of Gas Content on the Example of the Natural Manifestation of Gas in Tsuschar Village (Dagestan)

В данной статье даны особенности геологического строения района газопроявления «Цущар» в Кулинском районе на отложениях среднеюрского возраста, предлагается геолого-структурная схема возможного формирования залежи нефти и газа. Незначительные проявления газоносности, связанные обычно с минеральными источниками и подчиненные мощной толще юрских сланцев, развитых на значительных площадях нагорного Дагестана, начали обращать на себя внимание с 1931 г., в связи с поисками месторождений легких редких газов. Анализы газов показывают повышенное содержание легких редких газов в целом ряде месторождений нагорного Дагестана. Кроме группы месторождений Южного Дагестана известен пока только один выход горючего газа в Центральном Дагестане – Кулинском районе. На него указывает в своем рукописном отчете Дагестанскому Совнархозу геолог Н. М. Леднев. Этот выход подчинен юрским сланцам, связан с нарушениями неотектонического характера, образованными в результате сейсмической активизации региона. Цель исследования. Целью наших исследований является обоснование перспектив газоносности Горного Дагестана. На изучаемой территории отмечается наличие неправильных куполовидных складок с неожиданными направлениями их осей, пересекающими основное направление складчатости, частичными местными уклонениями в залегании пластов. Методы исследования. Основными методами исследования при изучении перспектив газоносности Горного Дагестана являлись геолого-структурный, стратиграфический, морфологический, тектонический и дешифрирование аэрофотоснимков. Результаты исследования. По сравнению с Предгорным Дагестаном и Прикумским районом, Горный Дагестан был подвержен более интенсивным геотектоническим движениям, неоднократно подвергался складчатости, испытал инверсию, со значительно большей амплитудой, что привело к усиленной денудации, развитию трещиноватости и разрывов, метаморфизму пород и органических образований. Все это отрицательно влияло на сохранение нефти и газа. Можно предполагать, что многие залежи, сформировавшиеся при прохождении продуцирующими толщами главной фазы нефтеобразования, были разрушены в периоды активизации тектонической деятельности на рубеже юры и мела, мела и палеогена. В дальнейшем шла генерация, преимущественно, газообразных углеводородов, которые при особенно благоприятных условиях могли сохраниться до настоящего времени. По результатам исследований можно утверждать, что газовое проявление Цущар могло проявиться в 1622, 1652 гг. в результате сильных землетрясений, эпицентр которых располагался в пределахисследуемого района This article describes the features of the geological structure of the Tsushar gas show area in the Kulinsky region on the Middle Jurassic deposits, and proposes a geological-structural diagram of the possible formation of oil and gas deposits. Minor manifestations of gas content, usually associated with mineral springs and subordinate to a thick stratum of Jurassic shales, developed over large areas of highland Dagestan, began to attract attention from 1931, in connection with the search for deposits of light rare gases. Gas analyzes show an increased content of light rare gases in a number of fields in highland Dagestan. In addition to the group of fields in Southern Dagestan, only one outlet of combustible gas in Central Dagestan is known – the Kulinsky region. It is pointed out in his handwritten report to the Dagestan Economic Council by the geologist N. M. Lednev. This outlet is subordinate to the Jurassic shale and is associated with neotectonic disturbances formed as a result of seismic activation of the region. Aim. The purpose of our research is to substantiate the prospects for gas content in Gorny Dagestan. In the study area, there are irregular dome-shaped folds with unexpected directions of their axes crossing the main direction of folding, partial local deviations in bedding. Methods. The main research methods in the study of the prospects for the gas content of Mountainous Dagestan were geological-structural, stratigraphic, morphological, tectonic and additional aerial photographs. Research results. Compared to Piedmont Dagestan and Prikumskiy region, Gorny Dagestan was subject to more intense geotectonic movements, repeatedly underwent folding, experienced inversion, with a much higher amplitude, which led to increased denudation, the development of fracturing and fractures, metamorphism of rocks and organic formations. All of this negatively affected the conservation of oil and gas. It can be assumed that many deposits, formed during the passage of the producing strata of the main phase of oil formation, were destroyed during periods of intensified tectonic activity at the boundary between the Jurassic and Cretaceous, Cretaceous and Paleogene. In the future, there was the generation of mainly gaseous hydrocarbons, which, under especially favorable conditions, could persist to the present day. According to the research results, it can be argued that the gas manifestation of Tsushar could have manifested itself in 1622, 1652. as a result of strong earthquakes, the epicenter, which was located within the study area