How you conduct yourself builds your personal brand so being professional and genuinely grateful for the opportunity to be considered for a position is part of that brand building The thank you note is a part of this.
Our suggestion is to:
Dear First Name:
I just wanted to write you a quick note to thank you for your time and say how much I enjoyed our conversation.
It appears that the position about which we spoke and my background and interests are great fits. I think this was brought out when we spoke about [please fill in].
Again, thanks for your time and please contact me if you have any questions or if I can be of any assistance now or in the future.