A C10 hydrocarbon composition of greater than 55 wt. % C10 mono-olefins containing from 11 to 45 wt. % 1-decene, at least 0.5 wt. % 2-butyl-1-hexene, at least 1 wt. % 3-propyl-1-heptene, from 0.5 to 12 wt. % 4-ethyl-1-octene, at least 4 wt. % 4-penten-1-yl-cyclopentane, and from 2 to 40 wt. % 5-methyl-1-nonene. A C12 hydrocarbon composition of greater than 60 wt. % C12 mono-olefins containing at least 8 wt. % 1-dodecene and at least 0.5 wt. % 6-hepten-1-yl-cyclopentane, and the composition also containing heptylcyclopentane and n-dodecane at a weight ratio of heptylcyclopentane to n-dodecane from 0:3:1 to 8:1. A C14 hydrocarbon composition of greater than 60 wt. % C14 mono-olefins containing at least 12 wt. % 1-tetradecene and at least 0.5 wt. % 8-nonen-1-yl-cyclopentane, and the composition also containing from 3 to 30 wt. % of n-tetradecane and nonylcyclopentane.