Pauling relation

The Nobel Prize chemist Linus Pauling related the mechanism of sickle cell anemia to a genetic defect in hemoglobin synthesis and thus defined the first molecular disease. Pauling s groundbreaking paper in 1949 was boldly titled Sickle Cell Anemia A Molecular Disease. Many claim that this discovery laid the foundation for molecular biology. What is the chemistry that is at the heart of this pioneering work ... 

The calculated shift of C-3 is 39.1 ppm as compared to an observed value of 39.45 ppm. Prediction of carbon chemical shifts using the Grant-Paul relation (4.1) is a practical aid in assigning the carbon signals of larger alkyl groups, e.g. in cholestane derivatives (Section 5.2.2). - Other increment systems have been proposed [201, 202], as well as an absolute scale for carbon shielding [203],... 

Pauling related the bond strengths to the electronegativity cA and c B of the two elements as... 

The Eley-Pauling relation [Eq. (3)] was first used in electrosorption studies by Conway and Bockris (14) to rationalize the dependence of observed standard rate constants for the HER (as exchange current densities) at various electrode metals on respective properties of the metals, such as their electronic work functions, electronegativities, and chemisorption energies for H, as mentioned earlier. 

This equation is evidently the same as the Pauling relation connecting bond distance and bond order, mentioned earlier in this section. A change of bond order by a factor of 2 corresponds to Aro 0.1-0.2 A. The new dissociation energy D o n) is... 

Fig. i. .3-1a,b Bethe-Slater-Pauling relation indicating the dependence of the mean magnetic moment per atom Pat on the average number of 3d and 4s electrons per atom for binary alloys with (a) fee stmeture and (b) bcc structure [3.6]... 

The bond extensions from equilibrium to transition-state configurations are given by a generalization of the Pauling relation between equilibrium bond lengths and bond orders, ... 

Using die values of electronegativity, Pauling further suggested that die fractional ionic contribution to the bond energy (FIG) is related to the electronegativities jca and xq in the A-B molecule and given by... 

The strengths of the monobasic acids increase rapidly with increase in oxidation state of the halogen in accordance with Pauling s rules (p. 50). For example, approximate values of pKa are HOCl 7.52, HOCIO 1.94, HOCIO2 - 3, HOCIO3 — 10. The pXa values of related acids increase in the sequence Cl < Br < I. 

INTERATOMIC DISTANCES AND BOND CHARACTER IN THE OXYGEN ACIDS AND RELATED SUBSTANCES By Linus Pauling... 

Pauling, L. Covalent Chemical Bonding of Transition Metals in Pyrite, Cobaltite, Skut-terrudite, Millerite, and Related Minerals Can. Mineral. 1978, 16, 447-452. 

This system is based on the observations (Pauling 1947) that a linear relation between single-bond radius and atomic number holds for bonds of constant hybrid character, and that for an element the single-bond radius is (at least approximately) linearly dependent on the d character of the dsp hybrid bond orbitals. 

The inclusion of both covalent and intermetallic crystals in Chapter 6 is predicated on the close relation between the covalent and metallic bonds, as discussed in Chapter 3. SP 54 and SP 55 are beautiful examples of the complexity of the atomic packing and bonding arrangements in alloy structures, which fascinated Pauling. 

It is possible to discuss the interatomic distances in relation to the valences of lead and thallium. From the system of metallic radii (Pauling, 1949) and the relation =DX-0-600 log n... 

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