Accession Number:

AD0625211

Title:

MAGNETIC ORDERING IN VF2.

Descriptive Note:

Technical rept.,

Corporate Author:

CHICAGO UNIV ILL DEPT OF CHEMISTRY

Personal Author(s):

• Stout,J. W.
• Boo,W. O. J.

Report Date:

1965-01-01

Pagination or Media Count:

12.0

Abstract:

The compound VF2 was prepared by treatment of vanadium metal with HF gas at 1250C to form VF3, and subsequent reduction to VF2 at 1150C with a controlled mixture of HF and H2. Debye-Scherrer photographs show VF2 to have the rutile structure, isomorphic with MnF2, FeF2, CoF2, NiF2 and ZnF2. Heat capacity measurements from room temperature to 5K, using a platinum resistance thermometer, show a peak in heat capacity at 7.0K, presumably associated with long-range magnetic ordering, and a large magnetic contribution to the heat capacity at higher temperatures. The major fraction of the magnetic entropy of R 1n 4 is acquired in the short range order region. The behavior of the magnetic entropy is similar to that found in CuC12 and CrC12 where there is extensive short-range magnetic ordering in one-dimensional chains of metal atoms coupled by relatively strong exchange forces.

Descriptors:

• *MAGNETIC PROPERTIES
• VANADIUM COMPOUNDS
• FLUORIDES
• CRYSTALS
• METAL CRYSTALS
• THERMAL PROPERTIES

Subject Categories:

• Physical Chemistry
• Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE