SiC is a covalent material in which both, Si and C atoms are sp$^3$ hybridized.
Each of the four sp$^3$ hybridized orbitals of a Si atom overlaps with one of the four sp$^3$ hybridized orbitals of the four surrounding C atoms and vice versa.
-This results in fourfold coordinated covalent $\sigma$ bonds of equal length and strength for each atom with its neighbours.
-Although the local order of Si and C next neighbour atoms characterized by the tetrahedral bonding is the same, more than 250 different types of structures called polytypes of SiC exist \cite{fischer90}.
+This results in fourfold coordinated covalent $\sigma$ bonds of equal length and strength for each atom with its neighbors.
+Although the local order of Si and C next neighbor atoms characterized by the tetrahedral bonding is the same, more than 250 different types of structures called polytypes of SiC exist \cite{fischer90}.
The polytypes differ in the one-dimensional stacking sequence of identical, close-packed SiC bilayers.
Each SiC bilayer can be situated in one of three possible positions (abbreviated a, b or c) with respect to the lattice while maintaining the tetrahedral bonding scheme of the crystal.
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