And as we mentioned earlier, graphite is a thick, three-dimensional stack of graphene sheets;the sheets are held together by weak, attractive intermolecular forces called van der Waals forces.

• 前面曾经提过，石墨是由石墨薄膜堆叠而成的三维厚片，而石墨薄膜层则是藉由凡得瓦力这种微弱的分子间引力吸附在一起。