Hydrogen and helium are the most abundant elements in the Universe. They are also, in
principle, the most simple. Nonetheless, they display remarkable properties under extreme …

▪ Abstract We know that giant planets played a crucial role in the making of our Solar
System. The discovery of giant planets orbiting other stars is a formidable opportunity to …

Almost 80 years ago it was predicted that, under sufficient compression, the H–H bond in
molecular hydrogen (H2) would break, forming a new, atomic, metallic, solid state of …

Metal hydrides are of inestimable importance for the future of hydrogen energy. This unique
monograph presents a clear and comprehensive description of the bulk properties of the …

Eighty years ago, it was proposed that solid hydrogen would become metallic at sufficiently
high density. Despite numerous investigations, this transition has not yet been …

Two new transition metal nitrides, IrN 2 and OsN 2, were synthesized at high pressures and
temperatures using laser-heated diamond-anvil cell techniques. Synchrotron x-ray …

Recent theoretical and experimental studies have produced several unusual and interesting
results on dense lithium, the first metal in the periodic table. These include the deviation from …

We used Raman and visible transmission spectroscopy to investigate dense hydrogen
(deuterium) up to 315 (275) GPa at 300 K. At around 200 GPa, we observe the phase …

Dense fluid metallic hydrogen occupies the interiors of Jupiter, Saturn, and many extrasolar
planets, where pressures reach millions of atmospheres. Planetary structure models must …

Using quantum simulation techniques based on either density functional theory or quantum
Monte Carlo, we find clear evidence of a first-order transition in liquid hydrogen, between a …