This project concerns electronic structure calculations by means of density functional theory. The project typically addresses materials mechanical integrity aspects related to stress corrosion cracking in nickel based alloys. This project is in cooperation with the Swedish Radiation Safety Authority. Non-equilibrium transients associated with nickel oxide effectively acts window for water permeation through a chromia depleted oxide scale, and this in the form of Ni(OH)2 at oxide grain boundaries. Thus, the oxy-hydroxides in the project title. Moreover, oxidation of the alloy by the hydroxide ions, results in creation of hydroxide vacancies that may accommodate the residual hydride ions, therefore oxy-hydroxy-hydrides in the title. The said transients as well as the fate of oxygen and hydrogen, being incorporated in the alloy grain boundaries, will be characterized. This will contribute to our emerging understanding of sensitization processes that precede mechanical failure in load baring components. The complexity of the problem is at a cross-road between catalysis, magnetism, electron conductivity, and even touches on essential properties of the cuprate- and novel nickelate superconductors.