Ball-and-stick diagram

EXAMPLE 7.1. Draw a ball-and-stick diagram depicting the reaction represented by the following equation ... 

Figure 2. Views of some carcinogenic molecules showing K- and bay- regions. Views are given of BP (I), DMBA (II), 3-methyl-cholanthrene (III), ll-methyl-15,16-dihydrocyclopenta[a]phen-anthracene (VII) and 5-methylchrysene (VIII). These and all subsequent ball-and-stick diagrams were drawn using the computer program VIEW (141).

Figures 4.2 L5 show accurate perspective ball-and-stick diagrams of the idealized structures in (4.45)-(4.49), in order to aid visualization of the rather unfamiliar shapes associated with equivalent sdM hybrids. Note that a surprising proportion of these hypothetical sdM geometries corresponds to placing all ligands on one side of a plane through the metal nucleus (see, e.g., Figs. 4.3(b) and (c) and 4.4(b) and (d)), and will thus be disfavored on steric or electrostatic grounds. Hence, the most reasonable structures are those shown in Figs. 4.3(a), 4.4(a) and (b), and 4.5(a) and (c), which have fewer cramped aacute angles and fill space more equitably.

Fig. 15. Ribbon and ball-and-stick diagrams of the NPl-CN structure. The view in (b) is rotated approximately 90° about the vertical axis from the view (a) on the left. The mobile loops are above and next to the heme in this view. Reproduced with permission from Ref. (.31).

FIGURE 7-41 Schematic ball and stick diagram depicting triad sequences. 

Figure 4. Ball-and-stick diagrams of the antibonding (left) and bond-centered (right) models for hydrogen donors in ZnO.

Fig. 10.47. Ball-and-stick diagrams of the structures of SiiooHx clusters obtained from simulated annealing, (a) Fully H-saturated SiiooHge (b) SiiooHeoi...

Draw a ball and stick diagram for the polyatomic molecules, anions or cations, including localised double bonds. 

In the same way the ball and stick diagrams of the remaining oxyacids and oxyanions may be considered, with appropriate expansion of the central element octet. 

Draw a ball and stick diagram. Associate the two H atoms with two of the terminal O atoms to form O to H single bonds, leaving the third O atom with only one covalent bond, namely a free valence, and convert it to a localised double bond. 

Q.5. Predict the shape of the covalent molecules by VSEPR theory and draw a ball-and-stick diagram to represent the structure, including regular or distorted angles. 

Fig. 5.15 Ball-and-stick diagram of a methanol molecule together with its infrared spectrum as a liquid. (From reference 26, with permission.)...

Figure 2.6. Polyhedral and ball-and-stick diagrams of a section of the olivine structure (two layers of 0 atoms thick).

A converged vinoxy X-A conical intersection was successfully located at 12.8 kcal/mol above the A-state equilibrium level,with geometry shown in the X-AJ column in Table 7.8. A B - conical interaction was similarly located at 12.2 kcal/mol above the B-state equilibrium, with geometry shown in the final column of Table 7.8. Figure 7.8 shows ball-and-stick diagrams of the CASNBO-optimized equilibrium and conical intersection structures for visual comparison. 

Figure 1 Ribbon diagram of four-helix bundle of MMOH from M. capsulatus (Bath) with the diiron active site depicted in ball-and-stick form (left). Ball-and-stick diagram of the MMOH, RNR-R2, and A9D active...

Figure 5.29 Representations of tetrahedra found in crystal structure diagrams (a) a ball-and-stick diagram of a tetrahedron, with a central silicon atom surrounded by four oxygen atoms and (b) its representation as a polyhedron. The views in parts (c), and (d) are the equivalent to those in parts (a) and (b), along the direction A in part (b), in which one tetrahedral vertex is uppermost. The views in parts (e) and (f) are the equivalent to those in parts (a) and (b), along the direction B in part (b), in which one tetrahedral edge is towards the observer...

Figure 8 Ball and stick diagram of the Val-Pro-Gly-Val sequence that defines a type-ll p-tum within the crystallographically determined structure of cyclo(Val-Pro-Gly-Val-Gly)3 (CCDC ID VPGVGB10). Note that the Vaf (CO) (HN)Val distance of 3.28 A is long compared to that typically observed for hydrogen-bonded structures within proteins (-2.9 A). In contrast, the Val 0) Pro (C) distance is relatively short, 2.77 A, and the nonbonded angle O (C=0) is relatively obtuse, 99.4°. These structural features are consistent with the presence of an n n interaction that stabilizes the type-ll p-tum within these elastin repeat sequences in combination with the n a interaction of hydrogen bond formation. Note the Cy-exo conformation of the Pro residue of the type-ll p-turn sequence.

Sketch or identify the sketch of a three-dimensional ball-and-stick diagram of any molecule for which a Lewis diagram can be drawn. 

Learning to form three-dimensional mental models of molecules and polyatomic ions is a skill you should develop while studying this chapter. The Lewis diagram is a convenient two-dimensional paper-and-pencU representation of the distribution of electrons in a molecule, but it has limited information. A goal to work toward is to be able to look at a Lewis diagram and then see a model of that species in your mind. Our emphasis on three-dimensional ball-and-stick diagrams in the examples that follow and in the end-of-chapter questions is meant to help you make the connection between Lewis diagrams and these mental models. If you have a molecular model kit, your models and the three-dimensional sketches you draw should match. 

Practice looking at the polar bonds within molecules and their net effect on overall molecular polarity whenever you draw Lewis diagrams or three-dimensional ball-and-stick diagrams. 

Let s examine this relationship between two-dimensional sketches and three-dimensional molecules a bit more carefully. Compare the following two Lewis diagrams for C3HgBrCl and the ball-and-stick diagrams beneath them ... 

Three structural diagrams and a ball-and-stick diagram of cyclohexane are... 

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