Lanthanum/aluminium oxide

M. Wilson and P. F. McMillan. Interpretation of X-ray and neutron diffraction patterns for amorphous yttrium and lanthanum aluminium oxides from computer simulation, Phjs. Rev. B 69, 54206-54217 (2004). 

Aluminium oxide, arsenic trioxide, bismuth trioxide, calcium oxide, chromic oxide, lanthanum oxide, lead dioxide, magnesium oxide, manganese dioxide, molybdenum trioxide, phosphorus pentoxide, stannic oxide, sulfur dioxide (explodes), tantalum pentoxide, tungsten trioxide, vanadium pentoxide. 

Lanthanum aluminate. Mechanochemical synthesis of lanthanum aluminate was carried out by the joint grinding of lanthanum oxide La203 with aluminium hydroxide or oxide in a planetary mill [20]. After activation for 120 min, a monophase product LaA103 with a large specific surface area was obtained. However, the formation of LaA103 was not observed when a-AI2O3 was used as an initial reagent. 

Oxides of the type RjO arc formed by all rare earth elements, by the ignition of the hydroxide, nitrate, sulfate, carbonate, or oxalate. In general the basicity decreases with increase of atomic weight, though yttrium and scandium are exceptions to the rule. The basicity of lanthanum approaches that of the alkaline earths, while scandium is about as basic as aluminium. 

Atomic spectrometric tests in air/acetylene flames a number of ions (like phosphate, sulphate, aluminium) decrease the emission and absorption signals of barium (and all of the alkaline earth metals). Adding an equal volume of a 25% solution of lanthanum chloride heptahydrate LaCl3 7H2O eliminates these interferences. Addition of lanthanum is not required if the nitrous oxide/acetylene flame is used. 

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