Unexpected persistence of cis-bridged chains in compressed AuF.

Raman scattering measurements indicate that cis-bridged chains are retained in AuF3 even at a compression of 45 GPa - in contrast to meta-GGA calculations suggesting that structures with such motifs are thermodynamically unstable above 4 GPa. This metastability implies that novel gold fluorides (e.g.

Volume expansive pressure (VEP) driven non-trivial topological phase transition in LiMgBi.

Topological Insulators (TI) exhibit robust spin-locked dissipationless Fermion transport along the surface states. In the current study, we use first-principles calculations to investigate a Topological Phase Transition (TPT) in a Half-Heusler (HH) compound LiMgBi driven by a Volume Expansive Pressure (VEP) which is attributed to the presence of, intrinsic voids, thermal perturbations and/or due to a phenomena known as cavity nuclei. We find that, the dynamically stable face-centred cubic (FCC) structure of LiMgBi (which belongs to the F4[combining macron]3m[216] space group), undergoes TPT beyond a critical VEP (at 4.

High-Pressure Phase Transitions of Zinc Difluoride up to 55 GPa.

Studying the effect of high pressure (exceeding 10 kbar) on the structure of solids allows us to gain deeper insight into the mechanism governing crystal structure stability. Here, we report a study on the high-pressure behavior of zinc difluoride (ZnF)-an archetypical ionic compound which at ambient pressure adopts the rutile (TiO) structure. Previous investigations, limited to a pressure of 15 GPa, revealed that this compound undergoes two pressure-induced phase transitions, i.

Utilization of doped GQDs for ultrasensitive detection of catastrophic melamine: A new SERS platform.

The detection and filtration of melamine in food products has become an emergence due to its harmful effect on humans. In present work, we have investigated the binding mechanism of melamine over carboxyl group edge-functionalized graphene quantum dots doped with oxygen and sulphur atoms (O-GQD and S-GQD). In order to monitor melamine, surface enhanced Raman scattering (SERS) is adopted which is an effective vibrational spectroscopic approach.