A gimmicky molecule created earlier this year was a great piece of science - but why not link the rings? This is the question posed by Professor Martyn Poliakoff as he discusses catenanes. More chemistry at http://www.periodicvideos.com/ Follow us on Facebook at http://www.facebook.com/periodicvideos And on Twitter at http://twitter.com/periodicvideos From the School of Chemistry at The University of Nottingham: http://www.nottingham.ac.uk/chemistry/index.aspx Periodic Videos films are by video journalist Brady Haran http://www.bradyharan.com/