Transition metals, naming binary compounds

The preceding method is sufficient for naming binary ionic compounds containing metals that exhibit only one oxidation number other than zero (Section 4-4). Most transition metals and the metals of Groups IIIA (except Al), IVA, and VA, exhibit more than one oxidation number. These metals may form two or more binary compounds with the same nonmetal. Ta distinguish among all the possibilities, the oxidation number of the metal is indicated by a Roman numeral in parentheses following its name. This method can be applied to any binary compound of a metal and a nonmetal. 

It should be noted that very little phase behavior data is available for ligands with CO2. Since p-diketones have been shown to be viable for the supercritical fluid extraction of a variety of metals, ranging from transition metals to lanthanides and actinides, we will focus on this set of compounds. In particular, the goal of this research is to determine the binary phase behavior of several P-diketones with CO2 because the phase behavior of the ligand/C02 systems is necessary for the design of in-situ chelation processes. Table I lists the lUPAC and abbreviated names for the p-diketones investigated here. These particular p-diketone ligands were chosen because they could be obtained commercially and have been used in a number of supercritical fluid extraction studies (1-4). 

Learning the names of binary covalent compounds may also be troublesome because of the variety of naming schemes that exist. Covalent compounds are those that are mostly formed between two or more nonmetals. Like the compounds of the transition metals discussed earlier, nonmetals can exist in a variety of oxidation numbers. Thus naming schemes have also been devised to distinguish between two or more different compounds formed between the same two nonmetal elements. Examples are the compounds formed between carbon and oxygen (CO and CO2). 

Ae metal complexes have been involved in polymerization processes of C=C containing compounds to different extents and in different circumstances. In this chapter, C=C cOTitaining monomers include three main subclasses (a) ethylene and related a-olefins, (b) styrene and conjugated dienes, and (c) what is often referred to as poW olefins, namely acrylates and methacrylates. For these three classes of monomers, Ae compounds have shown valuable, sometimes unique, abilities either as discrete compounds or in binary or even more comphcated tertiary combinations with other main group or transition metal compounds. Another essential distinction to be highlighted is the actual role of the Ae compounds in these processes they may be, as simply anticipated, the real active polymerization species, but they may be also involved in binary or tertiary combinations, as a partner component , undergoing tiansmetallation reactions with another metallic species which is in charge of polymerizatiOTi. 

---