Bear Stearns has split its interest rate and credit derivatives marketing groups as part of a push into the credit derivatives arena. Peter Croncota, senior managing director in New York, had been responsible for both groups, but the firm has now promoted Dan Hoffman, an interest-rate derivatives marketer in New York, to head up the rates area. Croncota referred calls to Karen Besa, spokeswoman in New York, who declined comment. Hoffman did not return calls.