Do I have a case for Defamation of Character?

i have recently been dismissed from my job because there was some money that went missing and they blamed me even though there was a possibility of about ten people that could have commited an offence.they had no evidence to incriminate me they just said that on the balance of probability that i had done even though i have not done anything wrong. i had worked for them for four years and i was one of there most trained and respected members of staff.anyway they had me arrested for this "offence" and the police cleared me of all charges because they had nothing that they could find to incriminatye me and i provided them all bank details and phone records etc to help with the enquiry. however the employer sent me a letter confirming my dismissal and they had originally alleged three things against me but this second letter confirmed that i had commited the offences even though they could not prove it. there has also been a member of staff telling everybody that im guilty do i have a case