Individual bond alignment

Smooth the CFS,q of the seed atom, i.e., apply individual bond alignment. 

Thus, individual bond alignment may be desirable. The first cause listed above is minimized by aligning every new bond as it is placed. However, if the initial direction of the chain is not directed along a principal axis (preceding section), this alignment will not occur, and errors may build up over the length of the chain. 

Individual bond alignment (IBA) of every bond as it is placed. 

The structure of PA6 has been investigated in detail and at least two crystal polymorphs, referred to as a and 7 have been identified [45,46]. The crystal packing of the a-polymorph consists of polymer sheets parallel to the (a,b)-plane. Within these sheets the PAG chains align anti-parallel, and are held together by hydrogen bonds. In the 7-form the polymer chains form sheets parallel to the (b,c)-plane but the individual chains align parallel. A third modification of PAG, the /3-form, has also been proposed [45,47-49]. Other authors state that the various structures found are just a or 7-structures with... 

Microorientation kIBA kVertCarbonyl Align individual bonds with axes. Make doubly bonded oxygens vertical. 

In the gas phase the dipole moment determined through Eq. (4.10) refers to an individual adsorbed particle. This is not so in the electrochemical situation. The dipole moment of an adsorbed species will tend to align neighboring solvent molecules in the opposite direction, thereby reducing the total dipole potential drop (see Fig. 4.3). Only the total change in dipole potential can be measured, and there is no way of dividing this into separate contributions from the adsorbate bond and the reorientation of the solvent. The apparent dipole potential of an ion adsorbed from a solution on a particular metal is often substantially smaller than that of the same ion adsorbed in the vacuum (see Table 4.1), since it contains a contribution from the solvent. For comparison we note that the dipole moments of alkali ions adsorbed from the vacuum are usually of the order of the order of 10 29 C m. 

Fig. 18. Disulfide bonding patterns in the aligned lipocalins. Individual strands of the P sheet are shown as rectangles, helices as ovals, and the disulfide bonds as connecting lines. Helix 3 does not occur in BBP and INS. Reproduced with permission from Ref (,48).

Bond polarity in a molecule can often be measured by a dipole moment, expressed in Debye imits (D). However, the physical measurement provides only the overall dipole moment, i.e. the snm of the individual dipoles. A molecule might possess bond polarity without displaying an overall dipole if two or more polar bonds are aligned so that they cancel each other out. The C-Cl bond is polar, but although chloroform (CHCI3) has a dipole moment (1.02 D), carbon tetrachloride (CCI4) has no overall dipole. Becanse of the tetrahedral orientation of the dipoles in carbon tetrachloride, the vector sum is zero. 

In an atom, the hybridization of s and p orbitals to form sp orbitals provides electron probability areas where bonds can form to make a molecule more stable than if the bonding had occurred in the individual s and p orbitals. The sp orbitals have one large lobe and one small lobe and are aligned along x, y, and z coordinates so that four sp orbitals, called sp3 orbitals because they are made of one s and three p orbitals, result in a tetrahedral-shaped arrangement. When there are three sp orbitals, made of one s and two p orbitals, called sp orbitals, the molecular has a triangular-planar shape. If there is bonding in two sp orbitals, made of one s and one p orbital, a linear molecule results. 

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