What is this anime about a green-haired robot named Sophie?
You're definitely thinking of SoltyRei.



There's Roy Revant (right), a bounty hunter who lost his daughter in the Blastfall (when a large building exploded).

Solty (middle), a Resemble (or artificial human), unlike anything the world has seen before...

And finally Rose Anderson (left), a thief who is revealed to be Rita Revant (Roy's daughter), shortly before her death.