Scientist, Spy, Genius: Who Was Bruno Pontecorvo? (2015)

I read this book recently and don't remember Close suggesting that Pontecorvo was misled or blackmailed by the USSR into defecting.

Instead, Close's theory is that the USSR legitimately-but-wrongly believed the net was closing in on Pontecorvo and speculated his post-defection treatment and apparent lack of trust came from him not being totally co-operative as a spy.