Valence and conduction bands
In solid-state physics, the valence band and conduction band are the bands closest to the Fermi level and thus determine the electrical conductivity of the solid. The valence band is the highest range of electron energies in which electrons are normally present at absolute zero temperature, while the conduction band is the lowest range of vacant electronic states. On a graph of the electronic band structure of a material, the valence band is located below the Fermi level, while the conduction band is located above it. This distinction is meaningless in metals as the highest band is partially filled, taking on the properties of both the valence and conduction bands.
Band gap
In semiconductors and insulators the two bands are separated by a band gap, while in semimetals the bands overlap. A band gap is an energy range in a solid where no electron states can exist due to the quantization of energy in quantum mechanics. Electrical conductivity of non-metals is determined by the susceptibility of electrons to excitation from the valence band to conduction band.
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by Todd Agnew
Fullness Found
by: Todd AgnewI?ve been walking around this world for some time
And I?ve found there are quite a few things to see
Physical and emotional and intellectual stimulations
But at the core I found them empty, empty
I?ve been trying so many things to fill me
But every one left me wanting
And every answer left me with more questions
And every road ended empty, empty
For every emptiness, a fullness may be found
For every lie there?s something true
For this broken cup that?s quickly leaking water
There is a fullness found in You, found in You
I?ve been working hard at what I thought was useful
But my hands are so small next to Yours
I?ve been trying to learn all that I thought would make me wise
But I just found vanity and lies
Until You, You opened my eyes and I saw
That for every emptiness, a fullness may be found
For every lie there?s something true
And for this broken cup that?s quickly leaking water
There's a fullness found in You, found in You
And I thought everything was meaningless
But now I?ve found that?s not true
And who am I to doubt the good in things
When all goodness comes from You, from You, my God
For every emptiness, a fullness may be found
For every lie there?s something true
And for this broken cup that?s quickly leaking water
There is a fullness found in You, found in You
The fullness found in You