Search results
Results From The WOW.Com Content Network
Slater-type orbitals (STOs) or Slater-type functions (STFs) are functions used as atomic orbitals in the linear combination of atomic orbitals molecular orbital method. They are named after the physicist John C. Slater , who introduced them in 1930.
It is a particular case of a Slater-type orbital (STO) in which the principal quantum number n is 1. The parameter ζ {\displaystyle \zeta } is called the Slater orbital exponent . Related sets of functions can be used to construct STO-nG basis sets which are used in quantum chemistry .
where n is the (true) principal quantum number, l the azimuthal quantum number, and f nl (r) is an oscillatory polynomial with n - l - 1 nodes. [5] Slater argued on the basis of previous calculations by Clarence Zener [ 6 ] that the presence of radial nodes was not required to obtain a reasonable approximation.
The use of Slater determinants ensures an antisymmetrized function at the outset. In the same way, the use of Slater determinants ensures conformity to the Pauli principle. Indeed, the Slater determinant vanishes if the set {} is linearly dependent. In particular, this is the case when two (or more) spin orbitals are the same.
STO-nG basis sets are minimal basis sets, where primitive Gaussian orbitals are fitted to a single Slater-type orbital (STO).originally took the values 2 – 6. They were first proposed by John Pople. A minimum basis set is where only sufficient orbitals are used to contain all the electrons in the neutral atom. Thus for the hydrogen atom, only a single 1s orbital is needed, while for a carbon ...
Unrestricted Hartree–Fock (UHF) theory is the most common molecular orbital method for open shell molecules where the number of electrons of each spin are not equal. While restricted Hartree–Fock theory uses a single molecular orbital twice, one multiplied by the α spin function and the other multiplied by the β spin function in the Slater determinant, unrestricted Hartree–Fock theory ...
In 1929 John C. Slater derived expressions for diagonal matrix elements of an approximate Hamiltonian while investigating atomic spectra within a perturbative approach. [1] The following year Edward Condon extended the rules to non-diagonal matrix elements. [ 2 ]
The Hartree–Fock electronic wave function is then the Slater determinant constructed from these orbitals. Following the basic postulates of quantum mechanics, the Hartree–Fock wave function can then be used to compute any desired chemical or physical property within the framework of the Hartree–Fock method and the approximations employed.