A composition comprising: a spray-dried catalyst composition comprising a transition metal catalyst component represented by the following formula: wherein: M is Fe, Fe, Co, Co, Co, Mn, Mn, Mn, Mn, Ru, Ru or Ru; X represents an atom or group covalently or ionically bonded to the metal M; T is the oxidation state of the metal; b is the valency of the atom or group X; and R 1 to R 7 are each independently selected from the group consisting of hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl, aryl, hydrocarbyl substituted aryl, heterohydrocarbyl substituted aryl, benzyl, hydrocarbyl substituted benzyl, heterohydrocarbyl substituted benzyland SiR' 3 where each R' is independently selected from hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl; and when any two or more of R 1 to R 7 are hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl, aryl, hydrocarbyl substituted aryl, heterohydrocarbyl substituted aryl, benzyl, hydrocarbyl substituted benzyl or heterohydrocarbyl substituted benzyl the two or more can be linked to form one or more cyclic substituents. a spray-dried catalyst composition comprising a transition metal catalyst component represented by the following formula: wherein: M is Fe, Fe, Co, Co, Co, Mn, Mn, Mn, Mn, Ru, Ru or Ru; X represents an atom or group covalently or ionically bonded to the metal M; T is the oxidation state of the metal; b is the valency of the atom or group X; and R 1 to R 7 are each independently selected from the group consisting of hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl, aryl, hydrocarbyl substituted aryl, heterohydrocarbyl substituted aryl, benzyl, hydrocarbyl substituted benzyl, heterohydrocarbyl substituted benzyland SiR' 3 where each R' is independently selected from hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl; and when any two or more of R 1 to R 7 are hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl, aryl, hydrocarbyl substituted aryl, heterohydrocarbyl substituted aryl, benzyl, hydrocarbyl substituted benzyl or heterohydrocarbyl substituted benzyl the two or more can be linked to form one or more cyclic substituents. M is Fe, Fe, Co, Co, Co, Mn, Mn, Mn, Mn, Ru, Ru or Ru; X represents an atom or group covalently or ionically bonded to the metal M; T is the oxidation state of the metal; b is the valency of the atom or group X; and R 1 to R 7 are each independently selected from the group consisting of hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl, aryl, hydrocarbyl substituted aryl, heterohydrocarbyl substituted aryl, benzyl, hydrocarbyl substituted benzyl, heterohydrocarbyl substituted benzyland SiR' 3 where each R' is independently selected from hydrogen, halogen, hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl; and when any two or more of R 1 to R 7 are hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, substituted heterohydrocarbyl, aryl, hydrocarbyl substituted aryl, heterohydrocarbyl substituted aryl, benzyl, hydrocarbyl substituted benzyl or heterohydrocarbyl substituted benzyl the two or more can be linked to form one or more cyclic substituents.