Yes, FRAGMENTATION is a Scrabble word!

Letter values in Scrabble US: F 4, R 1, A 1, G 2, M 3, E 1, N 1, T 1, A 1, T 1, I 1, O 1, N 1.

Is it a valid word?

FRAGMENTATION is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

separating something into fine particles
the disintegration of social norms governing behavior and thought and social relationships
(computer science) the condition of a file that is broken up and stored in many different locations on a magnetic disk
the scattering of bomb fragments after the bomb explodes

Not playable in Scrabble US: ATOMISATION.