Drawings perspective

The separation of a racemic mixture into its enantiomeric components is termed resolution The first resolution that of tartaric acid was carried out by Louis Pasteur m 1848 Tartaric acid IS a byproduct of wine making and is almost always found as its dextrorotatory 2R 3R stereoisomer shown here m a perspective drawing and m a Fischer projection... 

Fern-sprecher, m. telephone, -steuenmg, /. remote control, -wirkung, /. distance effect, action at a distance remote control, -zeich-Qung, /. perspective drawing. 

Figure 9. Perspective drawing of the crystal structure of Mn508. Small, filled balls represent the Mn4f ions small, open circles mark the positions of the Mn2+ ions. The oxygen atoms are shown as large, open circles.

During the last year we have built an FTMS instrument specifically designed for laser-induced thermal desorption from single-crystal surfaces. Figure 5 is a perspective drawing of the Instrument. The chamber is pumped by a 150 1/s ion pump and has a base pressure of 2.0 X 10- torr. Gases are Introduced through sapphire-sealed leak valves from a diffusion pumped gas manifold. 

Figure 5. Perspective drawing of the laser desorption FTMS instrument showing the relative positions of the crystal, the laser beam, and the FTMS analyzer cell. Reproduced with permission from Ref. 18. Copyright 1985, North-Holi and Physics Publishing.

This bibliography is similar to those of previous years.1 Perspective drawings for the structures are shown by using tapered bonds where... 

Figure 4. A perspective drawing of C.jH NjSi.B, with nonhydrogen atoms represented by thermal vibration ellipsoids drawn to encompass 50% of their electron density hydrogen atoms are represented by arbitrarily small spheres which are in no way representative of their true thermal motion.

A neo-modem perspective drawing on the complexity approach and Keynesian... 

Figure 23. Structures and perspective drawings of octosyl acids A and C.

Figure 2.19 Perspective drawing of a ternary system with a simple eutectic and no ternary compound. Reprinted, by permission, from Phase Diagrams for Ceramists, Vol. 1, p. 15. Copyright 1964, The American Ceramic Society.

Figure 2. Computer-generated perspective drawing of divinorin A (1) with crystallographic numbering scheme.

Fig. 2.3 ReOj-type structure (a) a perspective drawing (b) a projection of the atomic arrangement on (001) (c) and (d) a linkage pattern of octahedra.

In Figure 6 perspective drawings of Hartree Fock SCF orbitals are given. They reveal that the construction of MOs from the basis orbitals shown in Figure 4 leads to a reasonable description of SCF MOs, but their exact form can only be obtained from appropriate mixing of Walsh orbitals of the same symmetry. Worthy of note is the difference in shape of the 3e HOMOs ( 11 and 12) and the a, detailed description of the electronic structure and chemical bonding in 1. 

FIGURE 9. Perspective drawing of the calculated electron density distribution p (r) in the plane of the cyclopropane ring [HF/6-31 G(d,p) calculations]. Point p denotes the position of the bond critical point between two neighbouring C atoms. For better presentation, density values above 14 e A 3 are cut off... 

In Figure 9, a perspective drawing of the calculated HF/6-3 lG(d,p) electron density distribution p(r) in the plane of the C atoms of 1 is shown11. The electron density takes maxi-... 

Type II trajectories start at a point p in the internuclear region between two bonded atoms and end at one of the two nuclei in question. There are just two trajectories per bond, which together define a path of maximum electron density (MED path) that is visible in the perspective drawing of p r) shown in Figure 9. Each lateral displacement from the MED path leads to a decrease of p(r). The point p corresponds to the minimum of p(r) along the path and to a saddle point of p(r) in three dimensions. 

As shown by the formulas next to 5c and 6c, we are to understand that the horizontal bonds to the chiral center extend out of the plane of the paper, toward you, while the vertical bonds extend behind the plane of the paper, away from you. The overall translation of the projection formulas into the mirror-image, perspective drawings 5 and 6 may give you more trouble. The... 

Figure 5-12 Procedure for relating a projection formula to a configurational drawing with the aid of a ball-and-stick model. Assemble the ball-and-stick model over the projection formula (here 5c) so that the groups are arranged by the convention of the formula (horizontal bonds out, vertical bonds back), then turn the model so the appropriate groups, here CH3 and H, are parallel to the plane of the paper and make the perspective drawing agree with the model. The reverse procedure translates the perspective drawing into the projection formula.

The same information can be obtained from projection formulas. You can see that projections 19 and 20 are mirror images and that 20,21, or 22 can not be superimposed on 19. However, in some situations confusion can result in making such comparisons and it is important to be able to translate the projection formulas into ball-and-stick models or perspective drawings. 

Redraw the perspective drawings a, b, and c as Fischer projection formulas, leaving the configuration at the chiral centers unchanged. Similarly, redraw d and e in perspective, using a staggered sawhorse representation for e. 

Fic. I. Fe,C(CO),j, 1 (2). As will be the case for all perspective drawings in this survey, metal atoms are represented by larger filled circles, the carbide carbon atom as a small filled circle, and carbonyls as small open circles, with metal-metal bonds as heavy lines to emphasize the core geometry. Mean Fe-Fe distances apical-basal - 2.63 A, intrabasal = 2.66 A. Fewicrf-CMrt4de= 1.96 A, mean Fe -i-C.. = 1.89 A. The carbide carbon lies 0.08 A below the basal plane. 

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