This website has really interesting information on Kips Bay Plaza, completed in 1961. Let's just say that the exposed, deep concrete grid which combines interior and exterior and protects against glare and direct sun (and an atomic bomb, from the looks of it) --- uh, it might not be I.M. Pei's best work, right?
"combines both interior and exterior, structure and finish, into an integral whole"
"the deep concrete grid protects against glare and direct sun"
"the first exposed concrete residential buildings in New York City"