Virtual bond lengths

Figure 7. A section of the

Here h is the virtual bond length, the length of a monomer unit projected along the x axis, provided the pectin rod is parallel to that axis. If one replaced DP with the ratio of polymer molecular weight M to monomer residue weight, M, equation 8 is obtained. 

Figure 9 illustrates the best model according to the analysis. The chain is almost completely extended, since a virtual bond length of 4.25 A is almost equal to the advance per monomer of 4.22 A. Intramolecular hydrogen... 

For the above, detailed knowledge of chain architecture is not necessary. It is well known, however, that the modulus or of each polymer are strongly dependent on the detailed structure, actual and virtual bond lengths, rotational and valence bond angles, and the conformational isomeric states of the individual chains or segments. In a crystalline polymer, the highest elastic modulus is one parallel to the chain axis. The lowest modulus is in the plane transverse to the chain axis. In this plane the interactions are exclusively intermolecular in character and contain no intramolecular, covalent bonds. The intermolecular interactions may be common van der Waals dispersive forces, the somewhat... 

The pyrimidine ring is virtually flat. Its corrected bond lengths, as determined by a least-squares analysis of the crystal structure data for a unit cell of four molecules, are shown in formula (2) (60AX80), and the bond angles derived from these data show good agreement with those (3) derived by other means (63JCS5893) for comparison, each bond... 

Figure 4 Time step dependence of the average total energy for two models of a partially hydrated dodecamer DNA duplex. Thinner traces show results for virtually harmonic conditions when temperature was lowered to 1 K. The DNA molecule has fixed bond lengths, rigid bases, and fixed valence angles except for the mtra- and extracyclic bond angles m sugars, (a) No modifications of inertia (b) inertia modified as explained m the text. (From Ref. 54.)...

X-ray crystallographic studies are available on the ethoxy compound 1858 and on N,N-dimethylcyclopent[c]azepin-3-amine(19).59 The former is a fully conjugated, planar, 14k, non-benzenoid aromatic system, while the latter is virtually planar and, on the basis of bond length measurements, is best represented as the dipolar mesomer 19B. 

The Pt-Cl bond lengths in PtCl4- and PtClg- are virtually identical... 

Structure III makes virtually no contribution because of the positive formal charges on adjacent atoms and the overall higher formal charges. In HN3, the bond lengths are... 

Additionally, and interestingly, the DFT calculations suggest that the Zr-N bonds that lie on the same plane as the polymerization sites expand and contract according to the reaction coordinate of the ethylene insertion (2.23-2.34 A), while the Zr-O bond length remains virtually unchanged (Fig. 13). From studying these results, we... 

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