Structure and Physical Properties Cerium Pnictides

If one were to assign oxidation states to the cerium pnictides, a formulation of trivalent cerium and also P , As , Sb , and Bi would be straight- 

This prediction is a reasonable one for most cerium pnictides, namely CeP, CeAs, CeSb, and CeBi which, in fact, exhibit localized spin moments with an antiferromagnetic ordering of the 4/ electron remaining on each Ce [268]. CeN, however, is a metallic conductor with the corresponding magnetic properties and it only shows Pauli paramagnetism of the metallic electron gas, such that no local spin moment, characteristic for an unpaired electron, can be detected. This behavior leads to the possibility of an electronic formulation according to with one electron left in the conduction band, but 

4) On the other hand, pure LDA calculations are known to typically overestimate the itinerancy (that is, the delocalized behavior) of the 4/ levels, such that their exact energetic positioning must also be considered with a little caution. 

The electron density p(r) which emphasizes the frontier levels (b) clearly shows that the states just below p are centered along the directions of the Ce -Ce + interactions, and the remaining electron on cerium is localized in a cerium-cerium (partial) bond instead of being localized on the ion it- 

Fortunately, the DFT approach (LDA) used here is able to deal with that situation quantitatively [271]. In general, some caution is needed when 4/ levels are involved because of the severe problems mentioned before in the context of strong electronic correlation (see Section 2.13) which may render LDA-like calculations entirely useless. This was not the case for CeN, luckily. 

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