Accession Number:

ADA201596

Title:

Ferromagnetic Long Range Ordering in Copper(2) Maleate Monohydrate.

Descriptive Note:

Technical rept.

Corporate Author:

NORTH CAROLINA UNIV AT CHAPEL HILL DEPT OF CHEMISTRY

Personal Author(s):

• Padilla, Juan
• Hatfield, William E.
• Wasson, John R.
• Estes, William E.

Report Date:

1988-11-20

Pagination or Media Count:

21.0

Abstract:

The magnetic properties of copper II maleate monohydrate, CuC4H2O4 H2O, have been measured in the 1.8-66 K range. Magnetic susceptibility and isothermal magnetization measurements on powdered samples reveal a transition to a ferromagnetic state in this layered compound. The transition to the ordered state occurs at Tc 4.0 K. The positive value of 8.0 K for the Weiss constant in the paramagnetic region confirms the ferromagnetic nature of the interactions. The magnetic susceptibility data above 3Tc may be fit with a Heisenberg quadratic layer expression with the best fit parameters J 4.3cm, g 2.0, and zJ 0.42cm. The e.p.r. spectrum at room temperature indicates orthorhombic symmetry. A complex containing the isomeric form of the ligand, copper II fumarate dihydrate, has also been prepared and its magnetic properties determined in the 80-300 K range. Keywords Heisenberg quadratic layer Ferromagnetism superexchange Low dimensional compounds Long range ordering Carboxylate bridges Copper compounds Maleates. mjm

Descriptors:

• *HYDRATES
• *MALEIC ACID
• *COPPER COMPOUNDS
• REGIONS
• ROOM TEMPERATURE
• SPECTRA
• COPPER
• SAMPLING
• QUADRATIC EQUATIONS
• MAGNETIZATION
• FERROMAGNETIC MATERIALS
• ISOTHERMS
• POWDER METALS
• FERROMAGNETISM
• PARAMAGNETISM
• LAYERS
• SIZES(DIMENSIONS)
• MEASUREMENT
• MAGNETIC PROPERTIES

Subject Categories:

• Inorganic Chemistry
• Organic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE