Boron, Aluminum, Gallium, Indium, Thallium

12 Group IIIB (13). Boron, Aluminum, Gallium, Indium, Thallium 

Structure types have been established. Similar to Al, the M2X3 crystals (M = Ga, In, Tl X = S, Se, Te) are mostly based on M-defect tetrahedral structures, namely W (Ga2S3, In2Se3) and ZB (Ga2Se3, Ga2Te3, In2Te3). At atmospheric pressure, 283 can be present in three modifications. The low-temperature a-form is a cubic close-packed structure of S atoms, where 70% of the In atoms are randomly distributed on octahedral sites and the rest remain on tetrahedral sites. The P-form is related to the spinel structure, and the y-modification is hexagonal. 

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Property Boron Aluminum Gallium Indium Thallium... 

A. N. Nesmeyanov and R. A. SokoUk, The Organic Compounds of Boron, Aluminum, Gallium, Indium and Thallium, North-HoUand Publishing Co., Amsterdam, the Netherlands, 1967. 

Almond, M. J. Group 13 boron, aluminum, gallium, indium and thallium. J. Organomet. Chem. 2002, 30, 128-158. 

The poor metals among the BCNOs usually include aluminum, gallium, indium, thallium, tin, lead, and bismuth. The metalloids are boron, silicon, germanium, arsenic, antimony, tellurium, and polonium. The nonmetals are carbon, nitrogen, oxygen, phosphorus, sulfur and selenium. These groups are not official, and chemists sometimes disagree on whether a particular element like boron should be called a metal or a metalloid. 

Boron, aluminum, gallium, indium, and thallium are members of group 13 of the Periodic Table. Some important properties of these elements are given in Table 13.1.1. 

The Group 13 elements have the same relationship to the alkaline earth elements that the alkaline earth elements have to the alkali metals, that is, the group properties are modified by the presence of a third valence electron. The elements of Group 13 are boron, aluminum, gallium, indium, and thallium. Except for boron, which may be classified as a semimetal, these elements tend to show metallic properties. 

The Group IIIA elements consist of boron, aluminum, gallium, indium, and thallium. They have a valence shell configuration of ns r

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Most of the boron group elements exhibit a tripositive (3+) oxidation state however, they can be occasionally found in a unipositive (1+) state (with the exception of boron itself, which we describe in more detail later in this chapter). Keep reading to find out the details of five of the Group 13 (the 13th column on the periodic table) elements boron, aluminum, gallium, indium, and thallium. 

Indium is a member of the group 13 (formerly called IllA) elements along with boron, aluminum, gallium, and thallium. In aqueous solution, only In(lll) is stable, but compounds with I + and 2+ valences have been isolated [2], The ionic radius of In in sixfold coordination is 0.81 A in eightfold coordination, 0.92 A [3]. Although indium is not a transition metal, there are many aspects of its chemistry that resemble iron. The ionization potential, ionic radii, and coordination number of In are similar to Fe. The half-filled 3[Pg.402]

Organogermanium compounds containing germanium bonds to boron aluminum gallium, indium and thallium are included in this chapter. All metal derivatives are sensitive to air and moisture. 

Unlike boron, aluminum, gallium, and indium, thallium exists in both stable univalent (thaHous) and trivalent (thaUic) forms. There are numerous thaHous compounds, which are usually more stable than the corresponding thaUic compounds. The thaUium(I) ion resembles the alkaU metal ions and the silver ion in properties. In this respect, it forms a soluble, strongly basic hydroxide and a soluble carbonate, oxide, and cyanide like the alkaU metal ions. However, like the silver ion, it forms a very soluble fluoride, but the other haUdes are insoluble. Thallium (ITT) ion resembles aluminum, gallium, and indium ions in properties. 

This section will focus on homonuclear neutral or anionic clusters of the elements aluminum, gallium, indium, and thallium, which have an equal number of cluster atoms and substituents. Thus, they may clearly be distinguished from the metalloid clusters described below, which in some cases have structures closely related to the allotropes of the elements and in which the number of the cluster atoms exceeds the number of substituents. The compounds described here possess only a single non-centered shell of metal atoms. With few exceptions, their structures resemble those of the well-known deltahedral boron compounds such as B4(CMe3)4 [30], B9CI9 [31] or [B H ]2 [32]. The oxidation numbers of the elements in these... 

Homonuclear clusters of the heavier elements of the third main-group aluminum, gallium, indium and thallium having direct element-element interactions form a fascinating new class of compounds. As discussed in the previous Chapter 2.3, in some cases their structures resemble those known with the lightest element of that group, boron, while in other cases novel, metal-rich compounds were obtained which do not have any analogue in boron chemistry. 

With these elements, we begin our introduction to the p block, home of all nonmetals (and of a few metals) and of classic covalent chemistry. The elements are chemically rather diverse boron is a moderately electropositive nonmetal, whereas aluminum, gallium, indium, and thallium are all metals. The covalent chemistry we will encounter in this chapter, therefore, will still be somewhat limited, compared to what is to follow in the next chapters. Some general remarks are in order ... 

Group 13 (III A) includes boron (a metalloid) that has a nonmetal behavior, and aluminum, gallium, indium and thallium (poormetals). These elements have lower... 

The Group lllA elements clearly show the trend of increasing metallic character in going down any column of elements in the periodic table. Boron, at the top of Group lllA, is a metalloid, and its chemistry is typical of a nonmetal. The compound B(OH)3 is actually acidic (boric acid). The rest of the elements (aluminum, gallium, indium, and thallium) are metals, but their hydroxides change from amphoteric (acidic and basic) for aluminum and gallium to basic for indium and thallium. 

Among the group 3R elements, the -H3 oxidation state is the stable one for boron, aluminum, gallium, and indium. However, thallium, the heaviest element in the group, exists mainly in the T1+ state. 

Group 3A The boron group The group 3A elements have three valence electrons and include the metalloid boron and the metals aluminum, gallium, indium, and thallium. Boron and aluminum form 3+ ions, gallium and indium form both 3-1- and 1 -I- ions, and thallium forms only 1 + ions. 

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