Atomistically

adv. [f. prec. + -LY².] In atomistic manner; as composed of distinct atoms.

1874.  Watson & Evans, trans. Van Oosterzee’s Chr. Dogm., II. lxxiv. 400. So little can it [mankind] be atomistically individualised in its sins.

1881.  E. Thomas, trans. Lange’s Materialism, III. 215. Matter … whether we conceive it atomistically or as a continuum.