# Electronic Orbital Properties

rename
Updated
2009-03-12 00:13

## Quantum Numbers

Item | Property |
---|---|

n, l, m, ms | Each electron in an atom has its own unique set of these Quantum Numbers. This set of Quantum Numbers is like the Social Security Number for the electron. |

n | Shell Number = 1, 2, 3, 4, 5, 6, 7 for the known elements. |

n | Radial Quantum Number |

n | Principal Quantum Number |

n | Decides radius and energy of an orbital |

Larger n | Larger radius and larger energy |

Smaller n | Smaller radius and smaller energy |

l | Subshell Number = 0, 1, 2, 3, ..., n-1. |

l | Azimuthal Quantum Number |

l | Decides shape of an orbital |

l=0 | Quantum number for all s subshells |

l=1 | Quantum number for all p subshells |

l=2 | Quantum number for all d subshells |

l=3 | Quantum number for all f subshells |

m | Magnetic Quantum Number = -l, -l+1, -l+2, ..., l-2, l-1, l. |

m | Decides orientation of an orbital |

m_{s} | Electron Spin Quantum Number = -1/2 or +1/2. |

m_{s} | The Zeeman Effect in an applied magnetic field can distinguish values of this Quantum Number. |

Item | Property |
---|---|

n=1 | Contains 1s subshell |

n=2 | Contains 2s, 2p subshells |

n=3 | Contains 3s, 3p, 3d subshells |

n=4 | Contains 4s, 4p, 4d, 4f subshells |

Any s subshell | Contains 1 spherical orbital with no subscript |

Any p subshell | Contains 3 orbitals with subscripts x, y, z |

Any d subshell | Contains 5 orbitals with subscripts xy, yz, xz, x ^{2}-y^{2}, z^{2} |

Any f subshell | Contains 7 orbitals with subscripts xyz, x(z ^{2}-y^{2}), y(x^{2}-z^{2}), z(x^{2}-y^{2}),x ^{3}-(3/5)xr^{2}, y^{3}-(3/5)yr^{2}, z^{3}-(3/5)zr^{2} |

n | Number of subshells in the n-th shell |

n^{2} | Number of orbitals in the n-th shell |

2n^{2} | Maximum number of electrons in the n-th shell |

2l+1 | Number of orbitals in the l-th subshell |

2l+1 | Number of different m values in the l-th subshell |

2(2l+1) | Maximum number of electrons in the l-th subshell |

2 | Maximum number of electrons in an orbital |

n-1 | Number of Nodes in an (n)s orbital |

n | Gives the row in the periodic table for filling (n)s and (n)p subshells |

n+1 | Gives the row in the periodic table for filling (n)d subshells |

n+2 | Gives the row in the periodic table for filling (n)f subshells |

## Shells

Shell Number | Property |
---|---|

1 | contains 1 subshell: s only |

2 | contains 2 subshells: s and p |

3 | contains 3 subshells: s, p, and d |

4 | contains 4 subshells: s, p, d, and f |

n | contains n subshells |

1 | contains 1 orbital: one s orbital |

2 | contains 4 orbitals: one s and three p orbitals |

3 | contains 9 orbitals: one s, three p, and five d orbitals |

4 | contains 16 orbitals: one s, three p, five d, and seven f orbitals |

n | contains n^{2} orbitals |

1 | can hold up to 2 electrons |

2 | can hold up to 8 electrons |

3 | can hold up to 18 electrons |

4 | can hold up to 32 electrons |

n | can hold up to 2n^{2} electrons |

## Subshells

Subshell | Property |
---|---|

1s | contains 1 orbital |

2s | contains 1 orbital |

3s | contains 1 orbital |

4s | contains 1 orbital |

(n)s | contains 1 orbital |

2p | contains 3 orbitals |

3p | contains 3 orbitals |

4p | contains 3 orbitals |

(n)p | contains 3 orbitals |

3d | contains 5 orbitals |

4d | contains 5 orbitals |

(n)d | contains 5 orbitals |

4f | contains 7 orbitals |

(n)f | contains 7 orbitals |

Subshell | Property |
---|---|

1s | can hold up to 2 electrons |

2s | can hold up to 2 electrons |

3s | can hold up to 2 electrons |

4s | can hold up to 2 electrons |

(n)s | can hold up to 2 electrons |

2p | can hold up to 6 electrons |

3p | can hold up to 6 electrons |

4p | can hold up to 6 electrons |

(n)p | can hold up to 6 electrons |

3d | can hold up to 10 electrons |

4d | can hold up to 10 electrons |

(n)d | can hold up to 10 electrons |

4f | can hold up to 14 electrons |

(n)f | can hold up to 14 electrons |

Subshell | Property |
---|---|

1s | has electrons with n=1, l=0, m=0, m_{s}=±1/2 |

2s | has electrons with n=2, l=0, m=0, m_{s}=±1/2 |

2p | has electrons with n=2, l=1, m=-1,0,1, m_{s}=±1/2 |

3s | has electrons with n=3, l=0, m=0, m_{s}=±1/2 |

3p | has electrons with n=3, l=1, m=-1,0,1, m_{s}=±1/2 |

3d | has electrons with n=3, l=2, m=-2,-1,0,1,2, m_{s}=±1/2 |

4s | has electrons with n=4, l=0, m=0, m_{s}=±1/2 |

4p | has electrons with n=4, l=1, m=-1,0,1, m_{s}=±1/2 |

4d | has electrons with n=4, l=2, m=-2,-1,0,1,2, m_{s}=±1/2 |

4f | has electrons with n=4, l=3, m=-3,-2,-1,0,1,2,3, m_{s}=±1/2 |

## Filling of Subshells

Mnemonic:1s

2s 2p

3s 3p 3d

4s 4p 4d 4f

5s 5p 5d 5f

6s 6p 6d

7s 7p

The subshells fill diagonally from upper right to lower left in the chart above:First is 1s, then 2s, then 2p and 3s, then 3p and 4s.

Next comes 3d, 4p, and 5s. Then comes 4d, 5p, and 6s.

After that comes 4f, 5d, 6p, and 7s. Last comes 5f, 6d, and 7p.

For an atom with 118 electrons, the electron orbital configuration would be:

1s

The electron orbital configurations for atoms with less electrons will be truncated versions of this 118-electron configuration.
^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^{6}5s^{2}4d^{10}5p^{6}6s^{2}4f^{14}5d^{10}6p^{6}7s^{2}5f^{14}6d^{10}7p^{6}The total of the superscripts in an element's electron configuration equals

the total number of electrons in an atom of that element.

See Electron Configurations of Elements for many examples.

Subshell | General Order Filled(*) |
---|---|

Lowest Energy | 1st Filled |

Highest Energy | Last Filled |

1s | 1st |

2s | 2nd |

2p | 3rd |

3s | 4th |

3p | 5th |

4s | 6th(*) |

3d | 7th(*) |

4p | 8th |

5s | 9th(*) |

4d | 10th(*) |

5p | 11th |

6s | 12th(*) |

4f | 13th(*) |

5d | 14th(*) |

6p | 15th |

7s | 16th(*) |

5f | 17th(*) |

6d | 18th(*) |

7p | 19th |

(*) There are many exceptions to this order among the d- and f- Transition Elements

since (n+2)s, (n+1)d, and (n)f orbitals are close in energy when n is large.