Perfect ground form

DefinUioiis 6.S (a) A perfect ground form (of single coronoids), G, is a single coronoid with the... 

Abbreviations ig imperfect (ground form) o circular pg perfect (ground form)... 

Definition 6.4 . (a) A perfect higher member (of single coronoids) is defined by having the same formula as a Wold k > 1) circumscribed perfect ground form, (b) An imperfect higher member has the same formula as a A —fold circumscribed imperfect ground form. 

Formulas for Perfect Ground Forms and for Higher Members... 

Table 6.2. Formulas for perfect ground forms of single coronoids. ...

Figure 1 shows the smallest perfect ground forms (G ), one for each formula. The depicted isomers are those generated by the spiral walk. The reader is referred to Fig. 4.6, which shows the corresponding circular coronoids, 0, from which the ground forms are generated by two-contact additions of hexagons, one to each 0. 

Disodium Tetraborate Tetrahydrate. Disodium tetraborate tetrahydrate, Na I C TH O or Na20 2B203 4H20, formula wt, 273.27 monoclinic sp gr, 1.908 specific heat, ca 1.2 kJ/(kg K) [0.287 kcal/(g °C)] (61) heat of formation, —4.4890 MJ/mol ( — 1072.9 kcal/mol) (69) exists in nature as the mineral kemite and has a structural formula Na2[B40 (0H)2] 3H20. The crystals have two perfect cleavages and when ground, form elongated splinters. 

Instead of this elaborate specification of the (tiq 5q) formulas we shall be able to give a full account of them in terms of comprehensive spedfications and explicit expressions. All the three "pictures" are going to be invoked the Harary—Harborth—, the Balaban— and the new picture. But first some additional properties of the systems under consideration are needed. In this connection we shall introduce two subclasses of the ground forms and higher members perfect and imperfect. 

Figure 3 shows a dot diagram for the formulas of single coronoids as in Fig. 5.8. However, more detailed information about the extremal (A) systems is included formulas for ground forms and higher members, both perfect and imperfect, are indicated.

These modes of operation ate used in conjunction with the two most popular energy analyzers, the cylindrical mirror analyzer (CMA) and the concentric hemispherical analyzer (CHA). The most common form of the CMA used today is the double-pass version diagramed in Eigute 21. This device consists of two perfectly coaxial cylinders of radii r and r. The outer cylinder is held at a potential of (— ) and the inner cylinder is held at ground. The... 

In spite of the absence of periodicity, glasses exhibit, among other things, a specific volume, interatomic distances, coordination number, and local elastic modulus comparable to those of crystals. Therefore it has been considered natural to consider amorphous lattices as nearly periodic with the disorder treated as a perturbation, oftentimes in the form of defects, so such a study is not futile. This is indeed a sensible approach, as even the crystals themselves are rarely perfect, and many of their useful mechanical and other properties are determined by the existence and mobility of some sort of defects as well as by interaction between those defects. Nevertheless, a number of low-temperamre phenomena in glasses have persistently evaded a microscopic model-free description along those lines. A more radical revision of the concept of an elementary excitation on top of a unique ground state is necessary [3-5]. 

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