Intermolecular Forces I (van der Waals forces) The van der Waals force is the attractive or repulsive forces between molecules 偶极子 1.Ion-Dipole Attraction: Interaction between an ion and a dipole (a) (b) The Strongest in all intermolecular forces1. Ion-Dipole Attraction: • Interaction between an ion and a dipole Intermolecular Forces I (van der Waals forces Waals forces) The van The van der Waals force Waals force is the attractive or repulsive forces between molecules 偶极子 • Interaction between an ion and a dipole The Strongest in all intermolecular forces σ - σ +