The SeCl6 molecule, or selenium hexachloride, has a distinctive shape that can be understood through basic principles of molecular geometry.
In SeCl6, the selenium (Se) atom is at the center surrounded by six chlorine (Cl) atoms. The arrangement of these atoms is based on the VSEPR (Valence Shell Electron Pair Repulsion) theory, which states that electron pairs around a central atom will arrange themselves to minimize repulsion.
For SeCl6, selenium has a total of six bonding pairs with chlorine atoms and no lone pairs. This scenario leads to a octahedral geometry.
The bond angles in an octahedral molecule are all equal to 90 degrees between adjacent chlorine atoms. Additionally, the angles between opposite chlorine atoms are 180 degrees.
Thus, the shape of the SeCl6 molecule is octahedral with bond angles of 90 degrees and 180 degrees, showcasing a symmetrical distribution of the chlorine atoms around the selenium atom.