Can Silicon be part of a IONIC compound?!?

Question

Si(subscript=2)Cl(6)

Can that be named Silicon(III) cloride...

...My gut feeling is that it cant because it prabably is a Covalent compound...and as we know covalent compounds have NO ions..and would therefore be named by the greek system(disilicon hexacloride)...=/

Answer 1

Can Silicon be part of a IONIC compound?

No. Not in this case, or any compound that I know of.  Silicon combines with chlorine to make SiCl4 which is a volatile liquid at room temperature.  This would suggest that it is a molecular compound which does not form a network of Si and Cl atoms like silicon does with oxygen.  Of course the bonds in SiO2 are still covalent despite the formation of a network solid.

Further reactions of SiCl4 with Si and Cl2 produce Si2Cl6 and other combinations of Si and Cl.  The Si in Si2Cl6 would appear to have an oxidation number of +3.  

Since Si and Cl are both nonmetals, the conventional naming scheme would be using the Greek prefixes, rather than the Stock system.

The electronegativity difference between Cl and Si is 1.26 which is well below the current "cut off" of 2.00 for compounds which display ionic tendencies.  

It's interesting to find out that SiF4 behaves even less like an ionic compound than does SiCl4, even though the Si-F bonds in SiF4 have electronegativity differences of 2.08.

This reinforces the notion that electronegativites are a much more fluid than most people imagine.  The values given for electronegativities are averages, and the actual electronegativity for a given element may vary from one compound to the next.  For instance, the electronegativity of F in SiF4 is much less than 4.0.