Coupling constant with bond length, correlation

Cooperativity is more obvious in the coupling constants. The values for the terminal molecules continue to diminish as the chain grows beyond the dimer level. As in the case of the D atom, the coupling constants are smaller for the molecules in the middle of the chain. The authors noted a close linear correlation between the N quadrupole coupling constants and the lengths of the pertinent H-bonds. This same property was found to correlate also with the v stretching frequencies. 

Poraij-Koshits MA (1978) Structural effects of mutual influence of ligands in transition- and non-transition-metal complexes. Koordinatsionnaya Khimiya 4 842-866 (in Russian) Hartley FR (1973) The cis- and trans-effects of ligands. Chem SocRev 2 163-179 Russell DR, Mazid MA, Tucker PA (1980) Crystal structures of hydrido-tris(triethyl-phosphine)platinum(II), fluoro-tris(triethylphosphine)platinum(lD, and chloro-tris(trieth-ylphosphine)platinum(II) salts. J Chem Soc Dalton Trans 1737-1742 Blau R, Espenson J (1986) Correlations of platinum-195-phosphorus-31 coupling constants with platinum-hgand and platinum-platinum bond lengths. Inotg Chem 25 878-880 Belsky VK, Konovalov 1, Kukushkin VYu (1991) Structure of cis-dichloro-(dimethyl-sulfoxide)-(pyridine)platinum(II). Acta Cryst C47 292-294... 

Methylated trisilanes Me Si3Xg (X = H, F, Cl, Br, 1, Ph, OMe) can serve as model compounds for the study of correlations between structures and Si chemical shifts, Si Si coupling constants, bond strengths and bond lengths, as determined with vibrational spectroscopy and electron diffraction or for the study of rotational isomerism of Si-Si bonds. A report of these ongoing activities is given in this work. 

TT-backbonding, yet its CC-Si bond length [1.812(2) A] is not significantly shorter than that of the mean distance for all trimethylsilylethynyl metal complexes. Despite these uncertainties, the CC-Si bond distance bears close examination in future studies, particularly in conjunction with Si-NMR chemical shifts and MCC-Si nuclear spin-spin coupling constants, which have been reported to correlate with the extent of C-Si rr-bonding (184), because of the preliminary indication that it is shorter for metal-alkynyl complexes than in organic alkynes. 

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