Solid-state electronegativity of atoms: new approaches

Abstract

Electronegativities (EN) of 65 elements (H to Bi, except lanthanides and noble gases, plus U and Th) in solids were derived from various observed parameters, namely, bond energies in solids, structural geometry, work functions and force constants, yielding a set of internally consistent values. The solid-state electronegativities are generally lower than the conventional (`molecular') values, due to different coordination numbers and electronic structure in a solid versus a molecule; the decrease is stronger for metals than for non-metals, hence binary compounds have a wider EN difference and higher bond polarity (ionicity) in the solid than in the molecular (gaseous) state. Under high pressure, the ENs of metals increase and those of non-metals decrease, the binary solid becomes less polar and can ultimately dissociate into elements.

LModeA-nano: A PyMOL Plugin for Calculating Bond Strength in Solids, Surfaces, and Molecules via Local Vibrational Mode Analysis

“…In addition, this force field based method to calculate vibrational spectra has become obsolete due to the availability of DFT methods in calculating the lattice vibrations . (III) For some simple solid structures, force constants of chemical bonds can be calculated from empirical equations related to properties like effective nuclear charge, bond length, lattice energy, Madelung constant, and so forth. − (IV) For certain types of lattice structures (especially 2D materials), there exist analytical expressions between the bond stretching force constant and elastic properties (e.g., bulk modulus, Young’s modulus, and elastic constant). − (V) With the advent of the phonon calculation at the DFT level, one possible way to calculate the mean force constant ⟨ k ⟩ of the chemical bonds centered around one atom in solid is via where g ( E ) is the partial phonon density of states (PDOS) for the central atom, and E is the vibrational energy. − (VI) One commonly used computational method to get the force constant of a bond is to project the 3 × 3 matrix f AB collecting the force constants between two bonding atoms (A and B) into the direction parallel to this bond − where r A and r B are the Cartesian coordinates of two bonded atoms. This method appears intuitively reasonable because the matrix f AB indeed quantifies the real-space physical interaction between atoms A and B; however, f AB is simply an off-diagonal block of the full Hessian matrix f x (in Cartesian coordinates), while the diagonal blocks for atoms A and B are discarded.…”

In‐Situ Electronegativity and the Bridging of Chemical Bonding Concepts

“…[ 40 , 41 ] Others have relied on topological analyses of electron densities,[ 42 , 43 , 44 ] or various thermochemical and spectroscopical data. [ 45 , 46 ] Electronegativities of bonded atoms have also been evaluated from orbital analyses[ 47 , 48 ] and using various correction schemes to existing electronegativity scales. [ 49 , 50 ] Some approaches rely on electronegativity being defined as the chemical potential, as suggested by Iczkowski and Margrave.…”

Evolution of the structure of MSnO3 (M = Ba, Sr) perovskites during hydrothermal synthesis and their photocatalytic activity

“…We attribute this to the reduced electronegativity of the oxygen atoms of the terminal hydroxogroups. 31 With an increase in the firing temperature, the fraction of such atoms decreases, and at T > 400 °C, the behavior of the isomeric shift begins to correlate with the increasing ionicity of the structure. However, in our opinion, it is arguable that a significant number of OH groups are retained in the MSnO 3 or MSnO 3−0.5 x (OH) x perovskite phases up to high temperatures as a kind of point defect.…”