Changing focus after arriving to grad school?

[jmbky1]

I've been accepted to a couple of chemistry PhD programs and my initial interests while applying were in biochemistry. I was wondering if my area of focus shifted to maybe analytical or physical chemistry, would that be acceptable?

I'm sure many people have done it, but I don't want them to think I'm some type of indecisive flake. I'm not one of those guys who knew he wanted to be a biochemist from the time he was 10. If I visit and talk with faculty and find that I mesh better with, say, a physical chemist and his areas of research seem intriguing, would it not be a problem shifting to that?