In SiF62− and SiCl62−, which one is known and why?

[SiCl6]2−  does not exist as smaller Si cannot accommodate six large Cl− ions because of steric hindrance. SiF6-2 exists because of  the following reasons(i)Size of fluorine is small and its lone pair of electrons interacts with d-orbitals of Si strongly.(ii) Due to smaller size of F; steric repulsions will be less in SiF6-2​.(iii) Interaction of F lone pair electrons with Si is stronger than that of chlorine lone pairs.