Alkali metals group 1 compounds

Some of the alkali metal-group 15 element systems give compounds of stoichiometry ME. Of these, LiBi and NaBi have typical alloy stmc-tures and are superconductors below 2.47 K and 2.22 K respectively. Others, like LiAs, NaSb and KSb, have parallel infinite spirals of As or Sb atoms, and it is tempting to formulate them as M+ (E )" in which the (E )" spirals are iso-electronic with those of covalently catenated Se and Te (p. 752) however, their metallic lustre and electrical conductivity indicate at least some metallic bonding. Within the spiral chains As-As is 246 pm (cf. 252 pm in the element) and Sb-Sb is 285 pm (cf. 291 pm in the element). 

The niobium-arseitic compounds described here, with novel anionic structures, clearly demonstrate the many possibilities for stractural motifs in this system. Similarly high potential for diverse structures and properties should be expected for the heavier pitictides when combined with other transition metals and the alkali-metal group. 

The elements that form only one cation are the alkali metals (group IA), the alkaline earth metals (group IIA), zinc, cadmium, aluminum, and most often silver. The charge on the ions that these elements form in their compounds is always equal to their periodic table group number (or group number minus 10 in the newest labeling system in the periodic table). 

Several tri(cyclopentadienyl)tin(ll) and lead(ll) complexes have been prepared with alkali metal cations. The arrangement of Cp rings around the metal is in a paddle wheel configuration the alkali cation is bound to Cp and not Sn or Pb, further supporting the view of a weak alkali metal group 14 bond. Representative examples of these compounds include (77S-Cp)2E(/r-Cp)-Na(PMDTA) (E = Sn 230, Pb 231).239 240... 

The structure of the alkaline-earth metal compound CayC6o (for y < 5) follows the same space group Fm3m as for the heavy (M = K, Rb and Cs) alkali metal MxC6o compounds (x < 3) [27] and the Ca ions occupy both tetrahedral and octahedral sites. Because of the smaller size of the calcium ion, the octahedral sites can accommodate multiple Ca ions, and it is believed that up to three Ca ions can be accommodated in a single octahedral site [27]. Ba6C(jo and Sr6C60, in contrast, exhibit different crystal phases, such as the A15 and other bcc phases [28, 59],... 

Alkali Metal group 1 elements in the periodic table Li, Na, K, Rb, Cs, Fr Alkaline Earth Metal group 11 elements in the periodic table Be, Mg, Ca, Sr, Ba Alkaloid a nitrogen-containing compound obtained from plants, for example, caffeine, nicotine... 

Two lithium atoms each transfer a single electron to one sulfur atom to yield the ionic compound U2S. As an alkali metal (Group lA), lithium easily gives up its single valence electron. As a Group VIA nonmetal, sulfur readily accepts two additional electrons into its valence shell. 

When Cgo is treated with fluorine at elevated temperature, the reaction eventually leads to a product having the formula CToFeo. although fluorination under other conditions can lead to QoF - It is possible to reduce Ceo to produce negative ions known as fullerides. This can be accomplished electrochemically or by reactions with vapors of alkali metals. These compounds have the general formula M C60, and some compounds of this type are superconductors. It has also been possible to attach organic groups to the carbon atoms. 

Metal -nonmetal compounds and ammonium compounds (containing the NH4 group within a formula) are ionic. Other compounds are covalent, except that acids are ionized, some completely, when dissolved in water. The acids are named with a special system of their own, but pure binary acids can be named similarly to alkali metal-nonmetal compounds. 

Williams has described the chemistry of lithium as it relates to its psychiatric use (4,5). Alkali metals (Group lA) readily lose an electron from each atom to yield univalent cations. Most compounds of the... 

The reaction of barium with graphite is reported to form a mixture of insertion phases and BaCj. The insertion compound BaCe crystallized in the space group Pba/mmc, with a =4.302 and c = 10.51 A. The compound is less reactive than alkali-metal graphite compounds. ... 

The chemical reactivities of the alkali metal organometallic compounds (RM) vary widely depending on metal M, basicity of the solvent systems used, and steric and electronic properties of the organic group R. In many reactions an important factor is the stabilization resulting from formation of a delocalized carbanion system as in the polymerization of dienes or aromatic substituted ethylenes, and in Reactions 3, 4, 5, and 10 in Table I. It is primarily with these delocalized carbanion systems that this review is concerned although saturated organolithium compounds are discussed briefly. 

Alkali metals (Group lA) easily lose an electron to yield a univalent cation. Alkali metal compounds are almost entirely ionic, although lithium has rather more tendency to form covalent compounds. In solution, the very small diameter of lithium in relation to the aqueous solvent results in a large hydration sphere of... 

This section deals principally with binary derivatives of the alkali metals ternary compounds are omitted since they are considered, as appropriate, either elsewhere in this Report or in that covering the inorganic chemistry of the transition metals. Included here are subdivisions relating to hydrides, oxides and related species, and halides. Compounds of Group IV and V non-metals are not discussed because of the paucity of data. A separate section, entitled Molten Salts , dealing with the chemistry of molten halides (and nitrates) as solvents, is also included. 

There are relahvely few common strong bases. The most common soluble strong bases are the ionic hydroxides of the alkali metals (group lA) and the heavier alkaline earth metals (group 2A), such as NaOH, KOH, and C a(OH)2. These compounds completely dissociate into ions in aqueous solution. Thus, a solution labeled 030 M NaOH consists of 0.30 M Na iaq) and 0.30 M OH aq) there is essentially no undisstKiated NaOH. 

The alkali metals, group I, are the most strongly electropositive elements—the most strikingly metallic. Many of their compounds have been mentioned in earlier chapters. The alkaline-earth metals are also strongly electropositive. 

Element symbol, Li alkali metal, group 1 silvery white metal Z 3 A(r) 6.94 density (at 20°C), 0.53 g/cm m.p., 180.5°C reacts with water name derived from the Greek lithos, stone discovered 1817 used in low-melting alloys compounds have many uses, including ceramics and fungicides. 

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