lewis structure and vsepr

[An Dang 3F]

When determining, the vsepr of a molecule, do we have to draw the lowest energy Lewis structure of the molecule first and then determine the vsepr?

[allyz1F]

Drawing the Lewis structure usually helps to visualize what the actually VSEPR shape for the molecule is, but you can otherwise just memorize which shapes have how many bonds and lone pairs or use the notation (A= central atom, X= bonded atom, E= lone pair) to know which model a molecule is.

[StephanieRusnak]

you don't have to but it's very helpful

[Sabah Islam 1G]

Using the notation with (A= central atom, X= bonded atom, E= lone pair) is an alternative to drawing the lowest energy Lewis Structure because typically, molecules with the same AXE formula have the same general shape, so it may be helpful to understand which VSEPR shape coordinates to which AXE formula. Also, keep in mind that even though molecules with the same AXE formula have the same general shape, their bond angles may slightly differ.