Formation of layers and gas and liquid states of helium in 8-13 [angstrom] diameter pores of Y zeolites

Journal Article · Sun May 01 04:00:00 EDT 1994 · Journal of Low Temperature Physics; (United States)

DOI:https://doi.org/10.1007/BF00751786· OSTI ID:6823933

Wada, Nobuo ^[1]; Kato, Hideyuki; Watanabe, Takashi ^[2]

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1. Univ. of Tokyo (Japan)
2. Hokkaido Univ., Sapporo (Japan)

Evolution of layers and their motional states for [sup 3]He and [sup 4]He adsorbed in Y zeolites have been studied by means of isosteric heat of sorption and heat capacity measurements. The two kinds of Y zeolites used in this study have pores interconnected in an ordered fashion, as well as the same diameter 8-13 [angstrom]. However, they are different potential profiles on the pore wall. The heat of sorption clearly shows localization potentials at Na[sup +] ion sites on the pore wall for Na-Y zeolites. In contrast, Silica-Y zeolite has few localization sites because it contains very few cations. The authors find that a solid layer forms on the pore wall at 38% of full pore adsorption amount for both Y zeolites. Upon increasing the amount adsorbed, the adatoms on the solid layer behave as a gas whose molar heat capacity is a half of the gas constant. From 50 to 65%, the second layer on the pore wall is in a semi-quantum liquid state since the heat capacity becomes proportional to temperature. Finally, the possibility of Fermi degeneracy of adsorbed [sup 3]He in zeolitic micropores is discussed.

• OSTI ID: 6823933
• Journal Information: Journal of Low Temperature Physics; (United States), Journal Name: Journal of Low Temperature Physics; (United States) Vol. 95:3-4; ISSN JLTPAC; ISSN 0022-2291
• Country of Publication: United States
• Language: English

Related Subjects

665430* -- Other Topics in Quantum Fluids & Solids-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ADSORPTION HEAT
ENTHALPY
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
HELIUM 3
HELIUM 4
HELIUM ISOTOPES
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
ISOTOPES
LIGHT NUCLEI
MATERIALS
MINERALS
NUCLEI
PHYSICAL PROPERTIES
SILICATE MINERALS
SPECIFIC HEAT
STABLE ISOTOPES
THERMODYNAMIC PROPERTIES
ZEOLITES