And planar shape

Alumina Ceramic Electrolytes 17.3.7.1.2. Forming (Green) of Tubular and Planar Shapes. 

The rigidity and planar shapes of benzene rings and amide groups, along with the localized three-center H-bonds, suggests that the conformation of... 

Forming (green) of tubular and planar shapes by isostatic pressing, electrophoretic deposition, extrusion, and tape casting 18,... 

It is clear that simple cyclobutadienes, which could easily adopt a square planar shape if that would result in aromatic stabilization, do not in fact do so and are not aromatic. The high reactivity of these compounds is not caused merely by steric strain, since the strain should be no greater than that of simple cyclopropenes, which are known compounds. It is probably caused by antiaromaticity. ... 

The numbers on Fig. 7 refer to the number of unstable modes (corresponding to eigenvalues of the linearized form of (8) with positive real part) for shapes along segments of the families. Only the planar shape up the bifurcation point with the (lAe)>family and a portion of the (lAe)-family are stable to disturbances with the symmetry imposed by this sample size. 

Carrier generators in molecular conductors have been associated for a long time to a partial charge transfer between the HOMO (or LUMO) electronic band and other chemical species. These systems are known as two-component molecular conductors. Tetrathiofulvalene derivatives are versatile systems for the formation of molecular organic conductors due to their electron donor capacity by transferring one u-electron from the HOMO orbital, and to their planar shape that promotes their stacking as a consequence of the n-n orbital overlap. The electronic properties of these salts are essentially determined by the packing pattern of the donor molecules which, in turn, depends on the counter-ion. 

Chlorine pentafluoride and xenon tetrafluoride appear in Figure 9-26. Each has an inner atom with a steric number of 6, but their electron group arrangements include lone pairs. As a result, CIF5 has a square pyramidal shape, whereas XeF4 has a square planar shape. Pictures can help us determine whether or not the bond polarities cancel ... 

The degree of deformation and whether or not a drop breaks is completely determined by Ca, p, the flow type, and the initial drop shape and orientation. If Ca is less than a critical value, Cacri the initially spherical drop is deformed into a stable ellipsoid. If Ca is greater than Cacrit, a stable drop shape does not exist, so the drop will be continually stretched until it breaks. For linear, steady flows, the critical capillary number, Cacrit, is a function of the flow type and p. Figure 14 shows the dependence of CaCTi, on p for flows between elongational flow and simple shear flow. Bentley and Leal (1986) have shown that for flows with vorticity between simple shear flow and planar elongational flow, Caen, lies between the two curves in Fig. 14. The important points to be noted from Fig. 14 are these ... 

This molecule is of the AX3 type it has a trigonal planar electron-group geometry and a trigonal planar shape. 

It was pointed out by Poland and Knutson that some molecular structural features seem to be associated with high levels of both toxicity and receptor binding [70]. These include planarity and rectangular shape, halogenation at a minimum of three of the four lateral positions (2, 3, 7, and 8), but at least one unsubstituted ring position. Activity increases from fluorine to bromine. 

The required long planar shape is more readily supplied by simple disazo structures such as Cl Direct Blue 1 (4.60). Copper complexes of such disazo compounds are important and are dealt with elsewhere (section 5.5.3). A widely used method of producing A—A type disazo dyes relies on treating J acid with phosgene (COCl2) to give the bis-coupling component carbonyl J acid (4.61). 

The above treatment considers the ligands in an octahedral geometry (i.e. with the ligands placed at the centre of the faces of the cube). The square planar case is simply an extension of the octahedral where two ligands are removed from the z-axis. The repulsion of electrons in d.i and dx2 2 orbitals will not be the same and the result is a square planar shape. 

Unique structure type with square planar Hg4 and cube shaped Hg8 [4] Isotypical to KHg [4]... 

As a last example on the fabrication of silver clusters, it is worth mentioning that they can also be prepared in microemulsions, where the small droplets of water act as nanoreactors. The surfactant used was AOT and the reducing agent was a very mild one, i.e. sodium hypophosphite. In this manner, fluorescent silver clusters with less than ten atoms are formed and showed planar shape when deposited onto gold substrates, as determined by scanning tunneling microscopy [67, 68]. 

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