I am exploring the complex formation between ferric chloride and creatinine. However, I am unable to find any literature regarding this complex and the stoichiometric ratio of iron required for this complex formation.
I suspect it to form some sort of polymeric chelate. First try 1 to 1. You should probably heat it to drive off water and HCl. It will probably turn a very dark color.
Whenever you want to do a reaction whether it is organic, inorganic, organometallic or coordination complex, you should know about the nature of the reactants, the driving force, reaction conditions, thermodynamic consequences etc.
In this case, if literature is not available, be happy. Do some thing on your own.
Understand Acid-Base concepts and check the nature of donor and acceptor; whether
they are hard-soft, soft-hard, hard-hard or soft-soft pair. Then what are the donor centers and the preferred geometry for the metal ion with respect to a particular oxidation state. Enjoy your research like solving a puzzle with utmost interest and curiosity, pouring all your chemistry knowledge.