Hexaethylbenzene complexes of ruthenium and manganese X-ray crystal structures and NMR spectra of [(HEB)2Ru2(µ-Cl)3][C5(CO2Me)5], [(HEB)Ru(H2O)3][BF4]2, (HEB)RuCl2[P(OMe)3], trans-RuCl2(PMe3)4, and (HEB)Mn(CO)2Br