Orbital
An atomic orbital (also just an atomic orbit) is a function describing the spatial distribution of the possible occurrence of an electron of a given quantum state in the electron shell of an atom .
We cannot calculate or determine its exact location, but we can determine in what space it occurs. An orbital is a three-dimensional figure (part of space).
The negatively charged electron particles, which are in the shell of the atom, move quickly. A simplified negative charge model for the orbitals is used. The area of occurrence of the electron (orbital) is not sharply defined.
We cannot determine the exact path an electron travels, but we can tell where it is at a certain time, in a certain place. We can find frequent electrons in some places in the orbital. This means that it has different electron density in different places.
Orbitals[edit | edit source]
According to the shape, we recognize several types of orbitals, which we denote: s, p, d, f, (g) .
Orbitals s[edit | edit source]
There can only be two electrons in an orbital. The 1s orbital is spherically symmetric. The charge cloud of the 1s orbital is made up of electrons that occupy the lowest energy level.
The 1s orbital is shaped like a sphere centered in the atomic nucleus. If we start from the nucleus (in any direction), the electron density changes with increasing distance. The s orbital exists not only for the principal quantum number n = 1, but also for all other values of the principal quantum number. The larger volume is caused by higher layers with increasing principal quantum number.
Orbitals p[edit | edit source]
There are three 2p orbitals, all of which are dumbbell-shaped. An electron in the p level can choose between three 2p orbitals, which are labeled 2px, 2py and 2pz according to the coordinate axis in which direction the orbital is oriented. The 2p orbitals are rotationally symmetric. Any rotation about the coordinate axis covers the electron-dense orbital with itself.
Orbitals d[edit | edit source]
Each d orbital can be occupied by two electrons, there are a total of ten electrons in the 3d level.
- History
E. Rutherford (1911) created a new planetary model, according to which electrons orbit the nucleus in certain orbits. The Danish physicist N. Bohr expanded the theory on quantization. Dualistic nature of electron = has wave properties.
Between 1924 and 1927, the French physicist Broglie, the German physicist Heisenberg and the Austrian physicist Schrödinger developed the theory of wave (quantum) mechanics.
Quantum numbers[edit | edit source]
There are four quantum numbers to determine the state:
- principal quantum number n
- secondary quantum number l
- magnetic quantum number m
- spin quantum number s
Principal quantum number n[edit | edit source]
We determine the energy layer (n = 1 to n = 7) belonging to the given electron, which we denote by capital letters.
Secondary quantum number l[edit | edit source]
Shows the shape of the orbital, takes on values from 0 to (n − 1).
Magnetic quantum number m[edit | edit source]
The magnetic quantum number m in the orbital space determines the position. Values from -l through 0 to +I. Specifies the number of the orbital types. There is:
- one s orbital
- three p orbitals
- five d orbitals
- seven f orbitals
Spin quantum number s[edit | edit source]
Two electrons that have opposite values (spin) form an electron pair in an orbital. We perform the illustration:
- using symbols
We first state the main quantum number, then the symbol of the secondary quantum number and finally the number of electrons (written as an exponent).
- using boxes and symbols
The boxes contain as many boxes as there are orbitals of the corresponding type.
Links[edit | edit source]
Related articles[edit | edit source]
References[edit | edit source]
- WESTON, Trevor. Atlas lidského těla. - edition. Praha : Levné knihy KMa, 2003. ISBN 80-7321-092-4.
- ŠRÁMEK, Vratislav. Obecná a anorganická chemie. 2. edition. Olomouc : Nakladatelství Olomouc, 2002. ISBN 80-7182-099-7.
- GÄRTNER, Harald. Kompendium chemie : vzorce, pravidla a principy - úlohy a jejich řešení - periodická soustava prvků - výkladový slovník. 1. edition. [Praha] : Euromedia Group - Knižní klub, 2007. ISBN 978-80-242-2012-3.
