Paired & Parallel Configurations
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Paired & Parallel Configurations
Can someone explain to me what it means when Lavelle says that paired electrons have opposite spins and parallel electrons have the same spins? I'm trying to visualize it but it's hard picture.
Re: Paired & Parallel Configurations
In multi-electron atoms, electron-electron repulsion must be factored in when writing electron configurations. In a 2p subshell, for example, there are multiple orbitals, the 2px, 2py, and 2pz orbitals. Each of these orbitals cannot contain more than 2 electrons. However, the way these orbitals are filled is affected by electron-electron repulsion. When writing the configuration you should write the first electron as a part of the 2px orbital, but then the next electron should be written as a part of the 2py orbital, and the next electron as a part of the 2pz orbital. Only after each of these orbitals has one electron, do you go back and assign a second electron to an orbital of that subshell. When you write the first three electrons, one in each orbital, they are parallel to each other and each have the same spin. This would be shown as three half-arrows pointing upward, or three half-arrows pointing downward. The electrons added after the first three possess spins opposite to these. The arrows representing their spins will therefore point in the opposite direction. Each direction of spin is associated with a charge of +1/2 or -1/2. This arrangement of electrons when writing configurations is necessary if the lowest energy possible is to be achieved.
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Re: Paired & Parallel Configurations
It's similar to the notion of upper and lower arrow when you want to show electrons on a certain orbital. It's hard to visualize since it doesn't have classical picture.
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