2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/83946The quadrupole moment of a hydrogen atom in a magnetic field for field strengths from 0 to 4.414e13 G is calculated by two different methods. The first method is variational, and based on a single trial function. The second method deals with a solution of the Schroedinger equation in the form of a linear combination of Landau orbitals.4 pages, 1 figure, 1 table; RevTeX. Final (proofs-stage) version of the text; corrected numbers in Table 1 and in Eq.(15)Atomic PhysicsAstrophysicstext