I need to make several Iron compounds but I am having a bit of trouble finding a decent way to determine the oxidation state of Iron. I'm starting with a Iron(II) compound that I try to oxidize using several methods. I can use raman to determine the compound but that requires me to create the compound I want to make and check that spectrum against my experimental sample. This is quite a bit of work and I was hoping someone could point me towards a better solution. I can make an EDS but since my compounds usually contain carbon or oxygen as counter ion so EDS isn't very accurate. I don't (currently) have access to an XPS and I don't have unlimited access to a mass spectrometer (I have to travel quite a bit to get to one).
Can someone help me find a better way to determine the oxidation state??