Track composed by Alexander Brandon and Michiel Van Den Bos
This music plays when you visit a chateau owned by the mother of the Nicolette DuClare. Nicolette isn't as prominent a character in the original Deus Ex as she is in its sequel, Invisible War but she's definitely got one of the best tracks in the game: in fact, "Paris Chateau" (sometimes called "DuClare Chateau"), a collaboration between Alexander Brandon and Michiel van den Bos, is apparently his favourite tune in Deus Ex and "it was Michiel's first 5 patterns that got it started".
I've taken the first part of the UMX (the main DuClare Chateau theme) and then added the combat theme at 3:02. This is followed by the fourth and final passage at 4:22 which I believe is played when you're either having a conversation or leaving the zone.
I can see why Brandon enjoys this track as all components of it excel: the main theme is beautiful, dreamy and memorable and the combat theme really gets the adrenaline pumping. I also like the waltz that plays in the fourth part of the UMX file.