R. Marazza

Ternary rme2x2 alloys of the rare earths with the precious metals and silicon (or germanium)

Abstract The structural characteristics of about 30 compounds with the composition RMe2X2 have been studied for R = rare earth (or uranium), Me = rhodium, palladium, silver, iridium, platinum or gold and X = silicon or germanium. Their structures proved to be related to the Al4Ba (ThCu2Si2) types. The average atomic volumes of these phases are compared with those of similar groups of alloys and are briefly discussed. Special reference is made to the cerium and ytterbium compounds and the behaviour of these elements is compared with that shown in their binary alloys.

Lattice parameters of some ThCu2Si2-type phases in ternary alloys of rare earths with cobalt (or iron) and silicon (or germanium)

Abstract The structural characteristics of 19 compounds with the composition RMe2X2 have been studied for R = Y or a rare earth, Me = Fe or Co and X = Si or Ge. These compounds add to other similar rare earth alloys that are already known, resulting in the tI10 ThCu2Si2-type structure. The data obtained are briefly discussed.

A contribution to the crystal chemistry of ternary 1:1:1 alloys: RAgSn and RCuTl compounds (R ≡ rare earth)

Abstract The ternary alloys of the rare earths with tin and silver and of the rare earths with copper and thallium were studied for the stoichiometric ratio 1:1:1. The structures of these alloys are of the hP6 CaIn2 type. The trend in the average atomic volumes of these phases is compared with the trend in other series of isostructural compounds, and the general alloying behaviour of the rare earths in the ternary compounds is briefly summarized.

Lattice parameters oF RMn2Si2 and RMn2Ge2 compounds

Abstract The ternary compounds of the rare earths with Mn and Si in the stoichiometric ratio 1:2:2 have been prepared and studied by X-ray analysis. They were found to be of the tI10 Al4Ba-ThCu2Si2 structure type. A number of the previously known isostructural RMn2Ge2 compounds have also been prepared. The molar volumes of these phases are compared with those of other similar groups of compounds and are briefly discussed.

Ternary 1:1:1 alloys of nickel and palladium with tin and rare earths

Abstract Ternary alloys of the rare earths (R) with tin and nickel or palladium in the stoichiometric ratio 1:1:1 were studied. It was confirmed that these alloys have structures belonging to the CeCu2 family (oI12 (CeCu2) or oP12 (TiNiSi) types). The behaviour of the average atomic volumes of these phases is compared with the behaviour of other series of similar compounds, and the general properties of several RTSn alloys are briefly summarized.

Some phases in ternary alloys of thorium and uranium with the Al4Ba-ThCu2SI2-type structure

Abstract The geometrical characteristics of Al4Ba-ThCu2Si2-type phases are discussed briefly in terms of reduced cell parameters ( a R A ) . Special reference is made to those ternary compounds of Th and U which have this type of structure; the data already known from the literature and those now obtained for 21 new compounds are considered.

REInCd, REAsPd and RESbPt compounds (RE ≡ rare earth element)

Abstract The structural characteristics of a number of REInCd compounds (RE ≡ rare earth) and of the REAsPd and RESbPt compounds with the light rare earths were studied. These compounds have the hP6 CaIn2-type structure. The average atomic volumes are compared with those of other isostructural rare earth alloys and with those of a number of phases having the same formula but the cF12 MgAgAs-type structure.

Lattice parameters of RInZn and RPbCu ternary alloys of the rare earths

Abstract The ternary phases of rare earths alloyed with indium and zinc and with lead and copper in the stoichiometric ratio 1:1:1 were studied by metallographic and X-ray analyses. Their structural characteristics relative to the hP6 CaIn2-type structure are briefly discussed.

CaIn2-type and MgAgAs-type RESbPd compounds (RE rareearthelement)

Abstract We studied the ternary phases of alloys of the rare earths with antimony and palladium in the stoichiometric ratio 1:1:1. The alloys with lanthanum, cerium, praseodymium, neodymium, samarium, gadolinium and terbium proved to be of the hP6 CaIn2 type, whereas those with dysprosium, holmium, erbium, ytterbium and yttrium were of the cF12 MgAgAs type. The trends of the molar volumes are briefly discussed in relation to the molar volumes of isostructural compounds known already.

On the ternary rare earth alloys: RAuPb compounds

Abstract The ternary phases of rare earths alloyed with gold and lead in the stoichiometric ratio 1:1:1 were studied by metallographic and X-ray analyses. Their structural characteristics are briefly discussed and compared with those of all the 1:1:1 ternary phases pertaining to the CaIn2-type and the MgAgAs-type structures. The role of the dimensional factor in determining the structural type is examined.