Best:
Joshua Jackson/Katie Holmes-I have seriously never seen such better chemistry than with these two. I mean, they brought so much into to why i love Pacey and Joey so much. Half of my love for PJo is because they have so much damn chemistry and always always light up the screen and make everything so damn interesting. Their chemistry is so natural.
Ellen Pompeo/Patrick Dempsey-They had it in the beginning and they still haven't lost it after all this time.
Christopher Eccleston/Billie Piper
David Tennant/Billie Piper-Both of these men had great chemistry with her and she had great chemistry with both right back. Both pairs-in the reality of the show only one-made The Doctor and Rose what they are.
Sarah Michelle Gellar/James Marsters-There is hot stuff going on between them, even when they are enemies.
Joshua Jackson/Anna Torv-He doesn't have as much as with Katie Holmes, i think, but they still have enough that i just absolutely love their characters and keep hoping week after week that they get to be together.
Mark Sailing/Diana Argon-If they had any scenes this season, we would all be reminded just how great their chemistry really is.
Leonardo DiCaprio/Kate Winslet-Part of the reason Titanic was so good was because of the sizzling chemistry between these two.
Rupert Grint/Emma Watson-They may only be really good frienRAB in real life, but on screen they bring so much more and they make me happy that i am a Ron/Hermione shipper because they definitely have the chemistry and tension down.
Michael Biehn/Linda Hamilton-Since i just recently watched The Terminator for the first time about a week or so ago, i'm kind of on a Sarah Connor/Kyle Reese high and these two had enough chemistry that i wish we could have got more with them
Non-Romantic:
Joshua Jackson/John Noble-They have about the best Father/Son relationship i have ever seen on television and they both bring it every week in their scenes together.
Worst:
James Van Der Beek/Katie Holmes: Oh, where do i start with these two? They have the worse chemistry i have ever seen. They do, they really do. Not only is the Beek's character poorly written, so much so that he is so so easy to hate, but both characters are poorly written in their scenes together. And the actors do nothing to make them any more likable, with chemistry as flat as a soda, and awkward kissing scenes all the time, like they want so much to pull away, but can't because the script says they have to kiss. It always looks forced, tense-and not in a good way-and just flat flat flat.
Robert Pattinson/Kristen Stewart: Could their kisses on screen be anymore awkward?
Katherine Heigl/T.R. Knight: Ha. They were just a joke. Way way better off as frienRAB. They didn't bring anything to the screen.
Joshua Jackson/Meredith Monroe: Someone Josh doesn't have chemistry with. Lol. They were always kind of awkward together and their kisses just didn't seem to fit at all, making them look way to forced and so not right.
Nicholas Brendon/Anyone really...: Uh, he isn't very attractive, and i never felt anything when he was with Cordy, Willow or Anya. I just don't care about of those couples, because he doesn't have much chemistry with anyone.