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


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a201596.pdf


Report Date : 20 Nov 1988


Pagination or Media Count : 21


Abstract : The magnetic properties of copper (II) maleate monohydrate, Cu(C4H2O4) 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 = +4.3/cm, g = 2.0, and zJ' = +0.42/cm. 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