Solid solutions Ne–nD2. Diagram of phase equilibrium

Abstract

X-Ray investigations of vacuum condensates of the binary mixtures Ne–nD2 at temperatures from 6 K to the melting point of the solutions are performed. A diagram of phase equilibrium of the liquid and solid mixtures is proposed on the basis of the experimentally obtained and published data on the phase composition and mutual solubility of the components. The isotopic effect in the mutual solubility of the components is determined. A long-lived but metastable hexagonal phase is found, and the conditions for the formation and decomposition of this phase are determined.

Role of surface structure in photoelectron emission from solid Ne: Impurities, defect, and low-coordinated sites

“…For deuterium concentrations above 50 mole%, the amount of the fcc phase in the samples with condensation on a substrate at temperature 6 K is so small that within the sensitivity of the experiment only two hexagonal phases -hcp 1 and hcp 2 -were formed when the samples were condensed at low temperatures. The authors [38] referred to the estimates of the highest H 2 concentrations in solid Ne up to 10 %. The model we use, see Eq.…”

“…The degree of quantum effects is quantified by the de Boer quantum parameter which is 0.193, for D 2 , and 0.0918, for Ne [39]. The deuterium is also known to be soluble in rather large concentrations in solid Ne when deposited from the gas phase [37,38]. The tentative explanation of the electron emission increase with increase in the D 2 concentration is that lesser quantity of the terrace traps are available for the electrons which eventually appear at the low-coordinated step sites active with respect to the electron emission.…”

Mixing effects in the crystallization of supercooled quantum binary liquids

“…13 The slight differences in the occurrence of the onset of freezing in the pH 2 -Ne and oD 2 -Ne mixtures [compare Figs. 2(d) and 2(c)] may be partly related to the equilibrium D 2 -Ne phase diagram, 20 which shows a slight decrease of the liquidus temperature at small (<3%) Ne concentrations, in stark contrast to its increase observed in equilibrium H 2 -Ne mixtures. 17,18 For a discussion of the crystallization kinetics, we present in Fig.…”

“…The equilibrium solubility of neon in hydrogen in the liquid phase is limited to about 5%, and to about twice that value for neon in deuterium, whereas a phase separation occurs at higher Ne content. [17][18][19][20] The experimental conditions for all the mixtures investigated here are reported in Table I.…”

“…We point out that the slow crystallization from equilibrium H 2 -Ne and D 2 -Ne liquid mixtures results in a physical separation into pure Ne and H 2 (D 2 ) solid phases, where the amount of the fcc domains is negligibly small at such low Ne concentrations. [18][19][20] …”