Synthesis of Orthorhombic LaCuO

The orthorhombic phase of LaCu03, (0.43 d 0.5) is prepared in a manner similar to that for the monoclinic phase (above), but is obtained under more reducing conditions. Various oxygen stoichiometries can be obtained by quenching the materials from different temperatures or by reoxidizing the material at lower temperature. A sample of tetragonal or monoclinic LaCu03-a is added to a Pt crucible and placed into a tube 

The product is characterized by X-ray powder diffraction and thermo-gravimetric analysis. All diffraction lines could be indexed in orthorhombic symmetry, space group Pbam, a = 5.5491(1) k, b = 10.4782(2) A, c = 3.8796(1) A. TGA is consistent with the stoichiometry LaCu02.so- 

Submitted by MARGRET J. GESELBRACHT and ANGELICA M. STACY Checked by MATTHEW ROSSEINSKYt 

The partially deintercalated material, Li,Nb02, is the first example of a layered oxide containing an early transition metal that exhibits superconductivity. We report here the synthesis of superconducting samples of 

LixNb02 by partial deintercalation of the fully lithiated parent compound, LiNb02- The parent compound was first synthesized by Meyer and Hoppe by the reaction of Li20 with NbO and NbOj  

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