The Pauling notation (after Linus Carl Pauling ), also known as cell notation , box notation or box model , is a simple way of graphically listing atomic orbitals .
The orbitals themselves are represented in the box model by square boxes. Seamlessly adjoining boxes represent orbitals with the same secondary quantum number ( i.e. the same energy ). The s orbital is represented by one box, the p orbital by three adjacent boxes, the d orbital by five and the f orbital by seven Casket. Usually the height of the box above the abscissa corresponds to the energy content.
The occupation with electrons and the spin quantum number are shown with the help of arrows. An arrow in a box means that this orbital is occupied by an electron. Upward arrows indicate electrons with parallel spin , downward arrows indicate electrons with antiparallel spin. According to Hund's rule , all orbitals (boxes) have the same secondary quantum number, i. H. in the same energy level, easy to fill. Then the double occupation takes place with the electron with antiparallel spin.