Recently, the superconductivity in phosphine (PH3) has been discovered with the superconducting transition temperature Tc up to 203 GPa by using high pressure resistance measurements. However, the structural information of PH3 under high pressure remains elusive. Motivated by this, in this work, the behavior of PH3 under high pressure has been investigated by Raman spectroscopy at 298 K. The Raman spectra varied with pressure increasing, accompanying with the change of the sample color, which first became yellow, then red, and finally opaque. In the pressure range of 8.53–18.36 GPa, the decomposition of PH3 was observed, and the main decomposition products were P2H4 and element hydrogen (H2). Upon compression to higher pressure, the Raman signal of hydrogen vibration was observed to become stronger, indicating that PH3 or P2H4 further decomposed into element phosphorus and hydrogen. The original PH3 did not form again upon decomposition to ambient pressure. P2H4 and other decomposition products of compressed phosphine were considered as main products of the high temperature superconducting phase reported in experiment.

Phillyrin is an effective lignan glycoside extracted from a traditional Chinese medicine Forsythia suspensa (Thunb.) Vahl (Oleaceae). It mainly exists in the roots, stems, leaves and fruits of the plant, with the highest content in the leaves. In terms of its medicinal application, there are a large number of experimental data proving its pharmacological effects in vitro and in animal models, such as anti-inflammatory, anti-obesity, anti-tumor, etc. Furthermore, pharmacokinetic experiments have also shown phillyrin’s high effectiveness and low toxicity. Despite more than one thousand studies in the literature on phillyrin retrievable from Web of Science, PubMed, and CNKI, few reviews on its pharmacological activities have been presented conclusively. In this paper, we aimed to summarize the pharmacological and pharmacokinetic characteristics of phillyrin from the current literature, focusing on its anti-inflammatory, anti-aging, antiviral, antibacterial, hepatoprotective and anti-cancer effects, hoping to come up with new insights for its application as well as future studies.

Ammonium iodine (NH4I) as an important member of hydrogen-rich compounds has attracted a great deal of attention owing to its interesting structural changes triggered by the relative orientations of adjacent ammonium ions. Previous studies of ammonium iodide have remained in the low pressure range experimentally, which we first extended to so high pressure (250 GPa). We have investigated the structures of ammonium iodine under high pressure through ab initio evolutionary algorithm and total energy calculations based on density functional theory. The static enthalpy calculations show that phase V is stable until 85 GPa where a new phase Ibam is identified. Calculations of phonon spectra show that the Ibam phase is stable between 85 GPa and 101 GPa and the Cm phase is stable up to 130 GPa. In addition, ammonium iodine dissociates into NH3, H2, and I2 at 74 GPa. Subsequently, we analyzed phonon spectra and electronic band structures, finding that phonon softening is not the reason of dissociation and NH4I is always a semiconductor within the pressure range.

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The phonon spectrum of ordered zincblende Si 50 Ge 50 alloy is calculated by ab initio method. The energy band structure at zero pressure and the pressure dependence of phonon dispersion curves are shown up to 20 GPa. The calculation finds a pressure-induced softening of the transverse acoustic phonon mode and the mode frequency reaching zero at about 14 GPa, which indicate breaking of the symmetry and formation of a new phase under high pressure. phonon spectrum, Si 50 Ge 50 alloy, thermal-dynamical properties