Concept:Group IV semiconductor atoms (Si, Ge) have four valence electrons and share one electron with each of their four nearest neighbors to complete an octet, forming strong covalent bonds.
Formula:$$\text{Group IV Coordination: } 4 \text{ shared electron pairs} \implies s p^3 \text{ Covalent Bonds}$$
Solution:- Each silicon atom shares its 4 valence electrons with 4 neighboring silicon atoms.
- This forms eight shared valence electrons (four electron-pair covalent bonds) arranged in a tetrahedral diamond cubic crystal structure.
Why other options are incorrect:- Option A: Ionic bonding occurs between elements with large electronegativity differences via electron transfer (e.g., NaCl).
- Option C: Metallic bonding involves delocalized electrons in pure metals.
- Option D: Van der Waals forces are weak intermolecular attractions, not the primary covalent lattice bonds of semiconductors.
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