LANTHANIDE AND ACTINIDE OXIDES

Excellent overviews on the deposition methods of lanthanide and actinide oxides were published in several reviews by Niinisto" Zhang and Yan", Lee" and Yagi". ... 

TABLE 7. Deposition studies of lanthanide and actinide oxide films other than cerium oxide... 

Gabelnick, S. D., Reedy, G. T., Chasanov, M. G., Infrared spectra and stracture of some matrix-isolated lanthanide and actinide oxides, J. Chem. Phys., 60, (1974), 1167-1171. Cited on pages 119, 545, 649. 

The absence of reliable thermodynamic data for the tetrafluorides has contributed to difficulties in defining the chemistry of the rare earth elements. The fact that only Ce, Pr, and Tb form stable Rp4(s) phases has been established (see section 2.4) however, the thermochemistry of these fluorides has remained uncertain. Insight is provided by the work of Johansson (1978), who has correlated data for lanthanide and actinide oxides and halides and derived energy differences between the trivalent and tetravalent metal ions. The results, which have been used to estimate enthalpies of disproportionation of RF4 phases, agree with preparative observations and the stability order Prp4< TbP4 < CeP4. However, the results also indicate that tetravalent Nd and Dy have sufficient stability to occur in mixed metal systems like those described by Hoppe (1981). 

Magnetic properties of binary lanthanide and actinide oxides... 

Fig. 9. Comparison of stabilities of 3 + /2 + lanthanide and actinide oxidation states (stable 3 + ions at left, stable 2 + ions at right).

It is our purpose to present a summary of the compounds formed with oxygen and the lanthanide and actinide elements in such a way as to facilitate comparisons and contrasts. It is hoped that for many readers this summary will, in itself, prove useful by presenting an updated account of some relevant research concerning the lanthanide and actinide oxides. Beyond this, it will be found that the oxides afford a substantial platform upon which to assemble a comparative collage of lanthanide/ actinide chemistry. 

One final comparison can be made by looking at the oxides formed by Dy and Cf, which are electronic homologs. The oxide system of Dy is essentially that of Dy203, while with Cf, in addition to its sesquioxide, there are Cf70j2 and Cf02 (Cf02 is difficult to form, as is Tb02). Comparisons between other pairs of lanthanide and actinide oxides are also informative. 

A systematic treatment of data from the lanthanide and actinide oxides has generated estimated thermochemical values for the oxides of californium [126]. 

Lanthanide and Actinide Oxides, A Case Study in Solid State Chemistry, L. Eyring. In C.N.R. Rao (Ed.), Solid State Chemistry, Marcell Dekker, New York, pp. 564-634, 1974. 

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