Diatomic molecules bonding

Covalent Bonding II Diatomic Molecules Bond Lengths and Strengths... 

Provocative experimental evidence, at variance with conventional theory, is provided by the estimates of molecular diameters for diatomic molecules. Bonding theory requires the concentration of valence densities between the nuclei to increase as a function of bond order, in agreement with observed bond lengths (1.097, 1.208, 0.741 A) and force constants (22.95, 11.77, 5.75 Ncm-1) of the species N=N, 0=0 and H-H respectively. Molecular diameters can be measured by a variety of techniques based on gas viscosity, heat conductivity, diffusion and van der Waals equation of state. The results are in excellent agreement at values of 3.75, 3.61 and 2.72 A, for N2, O2 and H2, respectively. Conventional bonding theory cannot account for these results. 

Bonding in Heteronuclear Diatomic Molecules Bond properties... 

Strengths of Chemical Bonds, In CRC Handbook of Chemistry and Physics-, CRC Press Boca Raton. Tables with bond dissociation energies of diatomic molecules, bond dissociation enthalpies of polyatomic molecules, and standard enthalpies of formation of (mainly organic) radicals (at 298.15 K). The CRC Handbook is regularly updated, so the tables may vary according to the edition number. 

For diatomic molecules, bond enthalpies differ slightly from bond dissociation energies, and this difference can be determined using Equation 7.16 from Section 7.2 ... 

Bond Strengths In Diatomic Molecules Bond Strengths of Polyatomic Molecules Solubility of Copper and Copper Alloys Heat of Formation of Inorganic Oxides Phase Change... 

In a free atom, the electron density distribution is spherical, and centred on the nucleus, with the number of electrons equal to the nuclear charge. So diagrams often represent an atom by a point at its nucleus, the atom bearing a net charge of zero. In a homonuclear diatomic molecule, bonding electrons are shared equally between the... 

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