According to VSEPR Theory(Valence shell electron pair repulsion theory), with increase in electronegativity difference there is decrease in the bond angle, e.g. with NH3 and NF3 However, with PH3 and PF3 the case is just the reverse. Electronegativity difference between P and H is lesser than that between P and F, but contrarily the bond angle in PH3 is less than PF3. Why? A major told that it is due to p-pi d-pi back bonding. Please can anyone explain that to me?

Raunak Sarkar , 12 Years ago

Grade 10