A<unk>  <unk>  specifies the spatial distribution and energy of one (or one pair of) electron(s).<unk> st commonly an<unk>  is represented as a linear combination of atomic<unk> s (the LCAO-MO method), especially in qualitative or very approximate usage. They are invaluable in providing a simple<unk> del of bonding in<unk> lecules.<unk> st methods in computational chemistry today start by calculating the<unk> s of the system. A<unk>  describes the behavior of one electron in the electric field generated by the nuclei and some average distribution of the other electrons. In the case of two electrons occupying the same<unk> , the Pauli principle demands that they have opposite spin. Necessarily this is an approximation, and highly accurate descriptions of the<unk> lecular electronic wave function do not have<unk> s (see configuration interaction).
Molecular orbital
Idose
Theoretical plate
Concentration
Saturation 
Visible spectrum
Chemical symbol
Potential energy