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KJ: Josephson constant: K J = ... Hartree energy in eV E h = ... (Si) = 1.205 883 199 (60) × 10 −5 m 3 ⋅mol −1: u r (V m (Si)) = ...
≘ 2 625.499 639 4799 (50) kJ/mol ≘ 627.509 474 0631 (12) kcal/mol ≘ 219 474.631 363 20 (43) cm −1 ≘ 6 579.683 920 502 (13) THz. where: ħ is the reduced Planck constant, m e is the electron mass, e is the elementary charge, a 0 is the Bohr radius, ε 0 is the electric constant, c is the speed of light in vacuum, and; α is the fine ...
The T1 procedure reproduces these values with mean absolute and RMS errors of 1.8 and 2.5 kJ/mol, respectively. T1 reproduces experimental heats of formation for a set of 1805 diverse organic molecules from the NIST thermochemical database [14] with mean absolute and RMS errors of 8.5 and 11.5 kJ/mol, respectively.
Semi-empirical quantum chemistry methods are based on the Hartree–Fock formalism, but make many approximations and obtain some parameters from empirical data. They are very important in computational chemistry for treating large molecules where the full Hartree–Fock method without the approximations is too expensive.
In 1959, Shull and Hall [4] advocated atomic units based on Hartree's model but again chose to use as the defining unit. They explicitly named the distance unit a " Bohr radius "; in addition, they wrote the unit of energy as H = m e 4 / ℏ 2 {\displaystyle H=me^{4}/\hbar ^{2}} and called it a Hartree .
Note that the especially high molar values, as for paraffin, gasoline, water and ammonia, result from calculating specific heats in terms of moles of molecules. If specific heat is expressed per mole of atoms for these substances, none of the constant-volume values exceed, to any large extent, the theoretical Dulong–Petit limit of 25 J⋅mol ...
This Hartree–Fock model gives a reasonable description of H 2 around the equilibrium geometry – about 0.735 Å for the bond length (compared to a 0.746 Å experimental value) and 350 kJ/mol (84 kcal/mol) for the bond energy (experimentally, 432 kJ/mol (103 kcal/mol) [1]). This is typical for the HF model, which usually describes closed ...
In order to solve the equation of an electron in a spherical potential, Hartree first introduced atomic units to eliminate physical constants. Then he converted the Laplacian from Cartesian to spherical coordinates to show that the solution was a product of a radial function () / and a spherical harmonic with an angular quantum number , namely = (/) (,).