Comparisons bond angles

Search the literature for the experimental results for the H—O bond lengths and the H—O—H bond angle, and include a discussion of the comparison in your report. 

Fig. 1-6). The structure obtained for thiazoie is surprisingly close to an average of the structures of thiophene (169) and 1,3,4-thiadiazole (170) (Fig. 1-7). From a comparison of the molecular structures of thiazoie, thiophene, thiadiazole. and pyridine (171), it appears that around C(4) the bond angles of thiazoie C(4)-H with both adjacent C(4)-N and C(4)-C(5) bonds show a difference of 5.4° that, compared to a difference in C(2)-H of pyridine of 4.2°, is interpreted by L. Nygaard (159) as resulting from an attraction of H(4) by the electron lone pair of nitrogen. 

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... 

The mean of the values given for the C=C distance by the four principal maxima is 1.339 A. A similar comparison for the four principal maxima with curve B gives 1.346 A, Considering also the radial distribution value 1.34 A., we accept for the C=C doublebond distance in allene the value 1.34 = = 0.02 A. the C-H distance was assumed to be within 0.04 A. of 1.06 A. and the H-C-H bond angle close to 109°28, their independent evaluation being impossible because of the small contribution of the C-H terms to the diffraction pattern. 

According to the Haaland model, an increase of the Lewis acid-base interaction is accompanied by a decrease of both the R—Al—R bond angles and the Al—R bond distances. However, comparisons are possible only for adducts containing the same alane to exclude any steric or electronic effects of... 

Fig. 9 The experimentally determined geometries of thiirane- HC1 and thiirane- C1F drawn to scale. The n-pair model of thiirane is shown for comparison. The angle is slightly different in the two complexes for reasons discussed in [69]. The non-linearity 9 of the hydrogen bond is again greater than that of the halogen bond. See Fig. 1 for key to the colour coding of atoms...

Fig. 2.6 Comparison of the calculated structures for glycine in the gas-phase and in water (COSMO solvation model). Note that the central bond angle in the zwitterionic form 1 is distorted by the hydrogen bond length of 1.96A computed for this structure in the gas phase. When solvation effects are included in the calculation using COSMO, the electrostatic interaction is reduced in magnitude due to charge screening by water, and the bond angle distortion is no longer present.

Jiang, X., C-H. Yu, M. Cao, S. Q. Newton, E. F. Paulus, andL. Schafer. 1997. cfr/ifr Torsional Dependence of Peptide and Protein Backbone Bond-Lengths and Bond-Angles Comparison of Crystallographic and Calculated Parameters. J. Mol. Struct. 403, 83-93. 

Fig. 7.22 Comparison of calculated and observed (x-ray) mean N-C(a)-C bond angles for oligopeptides. Regions of and , of the most populated regions (N>3) of a set of oligopeptides selected as described in the reference quoted above.

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