Ring cluster

N. N. Greenwood, Boron Hydride Clusters, in H. W. Roesky (ed.) Rings, Clusters and Polymers of Main Group and Transition Elements, Elsevier, Amsterdam, 1989, pp. 49-105. 

Supplement to Mellor s Comprehensive Treatise on Inorganic and Theoretical Chemistry , Vol. V, Boron Part A, Boron-Oxygen Compounds , Longman, London, 1980, 825 pp. See also J. R. Bowser and T. P. Fehlner, Chap. 1 in H. W. Roesky (ed.). Rings, Clusters and Polymers of Main Group and Transition Elements, Elsevier, Amsterdam, 1989, pp. 1-48. 

H. Hoffmann and M. Becke-Goehring, Topics in Phosphorus Chemistry 8, 193-271 (1976) J. G. Riess in A. H. Cowley (ed.), Rings, Clusters and Polymers of the Main Group Elements, ACS Symposium Series No. 232, 17-47 (1983). 

Polynuclear aromatics (PNA) do not react in the FCC and tend to remain in coke. Adding hydrogen to the outer ring clusters makes them more crackable and less likely to form coke on the catalyst. 

In a ring cluster (a ring molecule) the number of edges is equal to the number of vertices (atoms) B = n, so we have ... 

In Rings, Clusters, and Polymers oftiie Main Group Elements Cowley, A. ACS Symposium Series American Chemical Society Washington, DC, 1983. 

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