Английская Википедия:Hartree

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The hartree (symbol: E_h), also known as the Hartree energy, is the unit of energy in the atomic units system, named after the British physicist Douglas Hartree. Its CODATA recommended value is Шаблон:Physconst = Шаблон:Physconst

The hartree is approximately the negative electric potential energy of the electron in a hydrogen atom in its ground state and, by the virial theorem, approximately twice its ionization energy; the relationships are not exact because of the finite mass of the nucleus of the hydrogen atom and relativistic corrections.

The hartree is usually used as a unit of energy in atomic physics and computational chemistry: for experimental measurements at the atomic scale, the electronvolt (eV) or the reciprocal centimetre (cm⁻¹) are much more widely used.

Other relationships

<math>E_\mathrm{h} = {\hbar^2 \over {m_\mathrm{e} a^2_0}} = m_\mathrm{e}\left(\frac{e^2}{4\pi\varepsilon_0\hbar}\right)^2 = m_\mathrm{e} c^2 \alpha^2 = {\hbar c \alpha \over {a_0}} </math>

= 2 Ry = 2 R_∞hc

= Шаблон:Val

= Шаблон:Val

= Шаблон:Val

≘ Шаблон:Val

≘ Шаблон:Val

≘ Шаблон:Val

≘ Шаблон:Val

where:

• ħ is the reduced Planck constant,
• m_e is the electron mass,
• e is the elementary charge,
• a₀ is the Bohr radius,
• ε₀ is the electric constant,
• c is the speed of light in vacuum, and
• α is the fine-structure constant.

Effective hartree units are used in semiconductor physics where <math>e^2</math> is replaced by <math>e^2/\varepsilon</math> and <math>\varepsilon </math> is the static dielectric constant. Also, the electron mass is replaced by the effective band mass <math>m^*</math>. The effective hartree in semiconductors becomes small enough to be measured in millielectronvolts (meV).