[(1,2,5,6-η)-1,5-Cyclooctadiene][(2,3,5,6-η)-2,3,5,6-tetramethyl-2,5-cyclohexadiene-1,4-dione]nickel

[(1,2,5,6-η)-1,5-Cyclooctadiene][(2,3,5,6-η)-2,3,5,6-tetramethyl-2,5-cyclohexadiene-1,4-dione]nickel