Structures with Text

Software for drawing and displa)dng chemical structures on microcomputers has been a growth area in the last year or two. Graphics for chemical structures, and integration of the structures with text or data, is the subject of a recent book. ... 

The era of integration of structures with text (77) was hardly beginning. 

Output data can be printed or exported to a spreadsheet. The rendering quality is very good. Structures can be rendered and labeled in several different ways. Molecular structures can be saved in several different formats or as image files. The presentation mode allows molecular structures to be combined with text. 

Figure 8.18 (a) Proposed pentagonal dodecahedral structure of Ti8C 2. (b) The same structure viewed as a Tig cube with each face capped by a C2 group, (c) An alternative structure (see text). 

Reaction Mechanisms In the first edition of this book, I introduced an innovative format for explaining reaction mechanisms in which the reaction steps are printed vertically, with the changes taking place in each step described next to the reaction arrow. This format allows a reader to see easily what is occurring at each step without having to flip back and forth between structures and text. Each successive edition has seen an increase in the number and quality of these vertical mechanisms, which are still as fresh and useful as ever. 

Table 4 Correlation of the number of classical structures with calculated bond lengths for Ceo and Cn. The bond environment column describes the arrangements of the carbon atoms which have the bond in common. The column labelled with a f is the bond order calculated using resonance theory as described in the text.

Fig. 2.46 EDPs from the incommensurate structures with [100] zone axis. (a) EDP shows spacing anomaly, (b) EDP shows orientation anomaly. (See text.)...

Fig. 2.112 Reciprocal lattice plane of rutile-typc structure with [111] zone axis. The (s, t) series of shear planes are indicated by dashed lines (see text). White circles are the possible shear planes for this system.

Answers from all of these searches contain CAS Registry Numbers. Answer sets may be combined, using the Boolean operators AND, OR, or NOT, with other answer sets or with text terms, such as names or molecular formulas. Any answer set also may be used to define subsets of the file for subsequent structure searching. Answer sets of up to 10,000 Registry Numbers from any type of search in this file may also be used as search terms in other files, such as the CA or CAOLD files (53). 

A]successful introduction for those who try to understand and explore biological macro-molecular structures...The text is loaded with many excellent didactic concepts and approaches."... 

Figure 21.8 Structural models for lamellar PEP-fr-PEO-b-PHMA block copolymer-aluminosilicate composite morphologies with a small PEP block. In the absence of the PEP block, the PEO (black) and PHMA (light grey) chains stretch into their respective domains while the aluminosilicate particles (white) partition into the hydrophilic PEO domain (a). Possible domain structures discussed in the text are illustrated as follows In the balls-in-lamellae structure the small PEP block (dark grey) forms round micellar domains (b). Dimple structure with PEP micelles at the PHMA/PEO-aluminosilicate interface (c). In the pillared-lamellae structure the PEP domains form pillars spanning across the PEO-aluminosilicate domain (d).37 (Reprinted with permission fiomG.E. S.Toombesetal., Chem. Mater. 2008,20,3278-3287. Copyright 2008 American Chemical Society.)...

Fig. 1.9. Proton nmr spectrum imported directly into ChemText. Chemical structures can be superimposed along with text, arrows, boxes, circles, etc.

Table I Proposed classification of hybrid materials, showing the dimensionality of different structures with respect to both organic connectivity between metal centers (O") and extended inorganic connectivity (I") (see text for explanation)...

The instrumental aspects of EPR have been summarized elsewhere, " although the text by Poole is especially noted for instrumental details and parameters. Obviously, to perform ENDOR experiments, one must have an EPR spectrometer, of which Bruker Biospin is the sole viable vendor at present (http //www.bruker-biospm.com/brukerepr/index.html accessed 03/01/2007). ENDOR accessories include the rf synthesizer and amplifiers and a microwave resonant cavity that includes rf cods in addition to the normal structure with field modulation coils. Locally constructed ENDOR spectrometers were more common in the past, with that of the late Clyde A. Hutchison Jr being a notable example, particularly for single-crystal studies. Such spectrometers still exist the author is familiar with those at Northwestern University. ... 

Table 5.20. Comparison of experimentally determined bond lengths with those calculated using the modified neglect of differential overlap method for the pentaborate structure (see text for data sources)...

CAS Registry is a structure and text-searchable database containing information on approximately 46 million organic and inorganic substances and over 60 million sequences with associated CAS registry numbers. 

CASREACT is a structure and text-searchable organic chemical reaction database containing more than 17 million single- and multistep reactions with more than six hundred thousand records from journal articles and patents with reaction information. Coverage is from 1840 to the present. 

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