Divalent and other metals

The spreading of the energy bands associated with the outer orbitals increases for the heavier elements, simply because of their larger size and consequently greater interaction. Because of this, the outer orbitals on most of the heavier elements in 

The most important characteristic of a metal is its ability to conduct electricity. The molecular orbital theory contains the idea that the electrons are delocalised throughout the crystal, which suggests that delocalised electrons are responsible for electrical conductivity. To develop this idea quantitatively it is necessary to use band theory. 

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