[pete_novo]

If you analyse the pi-electron system in methoxyethen (using the separation simplification), how would you explain using a simplified MO diagram for the pi-system the (C-O-C) bond angle of 120. VSEPR predicts around 104 (base: tetrahedral... two lones pairs...). I know it's hard to show MO diagrams on forums so i'm not asking for that! How can you show through an MO diagram that the bond angle is 120 by doing an analysis on the pi system. Also, does the pi system extend throughout the entire molecule?