Pnictogen Catalysis (image) Université de Genève Share Print E-Mail Caption The origin of the pnictogen catalysis: The large empty space, the "blue hole," on antimony, inside the molecule. Example: molecular model of Sb(C6F5)3, empty space in the molecule in blue. Sb = antimony. Credit © UNIGE Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.