Sp3/f hybrid orbitals

The fluorine sp3,77 hybrid [with 78.95% p character see Example 2.2] also has weak d-orbital contributions [0.12%] that can usually be ignored.) The polarization coefficients indicate that about 77.6% of the electron density is polarized toward the more electronegative F atom. 

The empty sp3 hybrid orbital overlaps with a filled orbital of F , which holds two electrons  

The Cl—F and Cl—Cl bonds in the cation are then formed by the overlap of the half-filled sp3 hybrid orbitals of the central chlorine atom with the half-filled p-orbitals of the terminal Cl and F atoms. Thus, by using sp3 hybridization, we end up with the same bent molecular geometry for the ion as that predicted by VSEPR theory (when the lone pairs on the central atom are ignored) 

Atoms in the second row (such as C, N, 0, and F) have one s orbital and three p orbitals in the valence shell. These orbitals are usually mixed together to give us hybridized orbitals (sp3, sp2, and sp). We get these orbitals by mixing the properties of s and p orbitals. What do we mean by mixing  

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