This article presents the results of two studies of Higgs boson properties using the final state, based on a dataset corresponding to 36.1 fb of TeV proton-proton collisions recorded by the ATLAS experiment at the Large Hadron Collider. The first study targets Higgs boson production via gluon-gluon fusion and constrains the CP properties of the effective Higgs-gluon interaction. Using angular distributions and the overall rate, a value of is obtained for the tangent of the mixing angle for CP-even and CP-odd contributions. The second study exploits the vector-boson fusion production mechanism to probe the Higgs boson couplings to longitudinally and transversely polarised and bosons in both the production and the decay of the Higgs boson; these couplings have not been directly constrained previously. The polarisation-dependent coupling-strength scale factors are defined as the ratios of the measured polarisation-dependent coupling strengths to those predicted by the Standard Model, and are determined using rate and kinematic information to be (stat.)(syst.) and (stat.)(syst.). These coupling strengths are translated into pseudo-observables, resulting in (stat.)(syst.) and (stat.)(syst.). All results are consistent with the Standard Model predictions.