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Nonbonding pair of electrons

The ternary Ge halides, MGeX3 (M = Rb, Cs X = Cl, Br, I) are polymorphic with various distorted perovskite-like (p. 963) structures which reflect the influence of the nonbonding pair of electrons on the Ge" centre. Thus, at room temperature, rhombohedral CsGel3 has three Ge-I at 275 pm and three at 327 pm whereas in the high-temperature cubic form (above 277°C) there are six Ge-I distances at 320 pm as a result of position changes of the Ge atoms (reversible order-disorder transition). Again, RbGel3 has a lemon-yellow, orthorhombic form below —92° an intermediate, bordeaux-red orthorhombic perovskite form (—92° to —52°) a black rhombohedral form (—52° to —29°) and... [Pg.376]

Examine electrostatic potential maps for methyl acetate (X=OMe), dimethylacetamide (X=NMe2), mdacetonitrile. What is die most electron-rich site in each molecule Does this site correspond to a bonding pair of electrons or a nonbonding pair of electrons Assuming that protonation occurs onto the most electron-rich site, where would you expect each molecule to protonate ... [Pg.150]

The carbon-oxygen double bond of a carbonyl group is similar in many respects to the carbon-carbon double bond of an alkene. The carbonyl carbon atom is s/ 2-hybridized and forms three valence electron remains in a carbon p orbital and forms a tt bond to oxygen by overlap with an oxygen p orbital. The oxygen atom also has two nonbonding pairs of electrons, w hich occupy its remaining two orbitals. [Pg.688]

Step 3. Place three nonbonding pairs of electrons on each outer atom, except H... [Pg.587]

There is more than one possibility they are nonstoichiometric but must be electrically neutral. clO-0142. Imagine making an O4 molecule by attaching an oxygen atom to the nonbonding pair of electrons on... [Pg.746]

Hydrogen bonds require electron-deficient hydrogen atoms in polar H—X bonds and highly electronegative atoms with nonbonding pairs of electrons are present. Use Lewis structures to determine whether these requirements are met. [Pg.765]

Because the breadth of chemical behavior can be bewildering in its complexity, chemists search for general ways to organize chemical reactivity patterns. Two familiar patterns are Br< )nsted acid-base (proton transfer) and oxidation-reduction (electron transfer) reactions. A related pattern of reactivity can be viewed as the donation of a pair of electrons to form a new bond. One example is the reaction between gaseous ammonia and trimethyl boron, in which the ammonia molecule uses its nonbonding pair of electrons to form a bond between nitrogen and boron ... [Pg.1499]

The repulsion between nonbonding pairs of electrons is greater than that between bonding pairs of electrons. [Pg.19]

Structural diversity is achieved through the use of nonbonded pairs of electrons on the ligand of both type II complexes to coordinate additional metal atoms. The S—S distances of known complexes range from 1.98 to 2.15 A. Most S—S distances are intermediate between the distance of 1.89 A for Sj ( Zg ) (104) and 2.13 A for ( Zg+) in Na2S2 (50). The main S—S distances show no clear systematic trend with structural type (cf. Table II). [Pg.111]

If the nucleophilic site (HOMO) involves a nonbonded pair of electrons (path a), a stable covalently bonded complex will form. If the HOMO is a a bond, direct reaction is unlikely unless the bond is high in energy and sterically exposed, as in a three-membered ring, but if the bond is to H, hydride abstraction may occur (path b, steps 1 and 2) or a hydride bridge may form (path 6, step 1). The last two possibilities are discussed further in Chapter 10. If the HOMO is a n bond, a n complex may result (path c, step 1), or, more commonly, donation of the n electrons results in the formation of a a bond at the end where the n electron density was higher, the other end becoming Lewis acidic in the process (path c, steps 1 and 2). The effects of substituents on olefin reactivity were discussed in Chapter 6. [Pg.107]

Substituent An atom or nonbonding pair of electrons surrounding a central atom. [Pg.212]

The trans structure is expected for R < 0.7 (Figure 25), the two important experimental cases being [M(lone pair)2(unidentate)4] and [M02(unidentate)4]. Compounds containing two nonbonding pairs of electrons and four unidentate ligands are invariably observed to be square planar,... [Pg.52]

Structural diversity is exhibited through the utilization of the nonbonded pairs of electrons on the S2 ligand of both type I and type II complexes to coordinate additional metal atoms. [Pg.535]


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See also in sourсe #XX -- [ Pg.165 ]




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Electron nonbonding

Electrons nonbonded

Nonbonded electron pair

Nonbonding electron pairs

Nonbonding pairs

Of electron pairs

Pairing of electrons

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