2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/63749We give a natural construction of unramified over Z framed mixed Tate motives, whose periods are the multiple zeta values. Namely, for each convergent multiple zeta-value we define two boundary divisors A and B in the moduli space M_{0,n+3} of stable curves of genus zero. The corresponding multiple zeta-motive is the n-th cohomology of the pair (M_{0,n+3} -A,B).Corrected version, 20 pages, 4 picturesAlgebraic GeometryNumber Theorytext