Element Group 15 (IMAGE) Universität Bayreuth Caption Section from the periodic table: Nitrogen (red) and the heavier elements phosphorus, arsenic, antimony and bismuth (green) belong to the element group 15. Under extremely high pressures, nitrogen, like these other group members, has a structure consisting of zigzag-shaped two-dimensional layers. Left and right are the groups 14 and 16, headed by carbon and oxygen. Credit Image: Dominique Laniel. Usage Restrictions None License Licensed content 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.