A Homogenous Charge Compression Ignition engine is used in conjunction with a hybrid powertrain. A gating element within a stage of a programmable delay element suppresses an operation of other stages of the delay element. Such a stent is particularly suited for use in ostial regions, which require greater support near the end of the stent. Biscyclopentadienyl ligand systems which have such a substitution pattern and can be used for preparing these organometallic transition metal compounds are also provided.