The features of electron deficient compounds Example a.forming coordination compound HBF4 HF→BF3 Example b.forming Al2Cl6 molecules in gas phase Al:ns2npl C (sp3杂化) Cl:2s22p5 Cl Cl Al Cl Cl Cl Cl Al The features of electron deficient compounds Example b. forming Al2Cl6 molecules in gas phase HF BF3 Example a. forming coordination compound HBF4 Al：ns2np1 (sp3杂化) Cl：2s22p5