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Buckled monolayer nitrogene has been recently predicted to be stable above the room temperature. The low atomic number of nitrogen atom suggests, that spin-orbit coupling in nitrogene is weak, similar to graphene or silicene. We employ first principles calculations and perform a systematic study of the intrinsic and extrinsic spin-orbit coupling in this material. We calculate the spin mixing parameter [Formula: see text], reflecting the strength of the intrinsic spin-orbit coupling and find, that [Formula: see text] is relatively small, on the order of [Formula: see text]. It also displays a weak anisotropy, opposite for electrons and holes. To study extrinsic effects of spin-orbit coupling we apply a transverse electric field enabling spin-orbit fields [Formula: see text]. We find, that [Formula: see text] are on the order of a single [Formula: see text]eV in the valence band, and tens to a hundred of [Formula: see text]eV in the conduction band, depending on the applied electric field. Similar to [Formula: see text], [Formula: see text] is also anisotropic, in particular for the conduction electrons., (© 2022. The Author(s).)

As part of the experiments herein, the mechanical properties of specimens made of poly-ether-ether-ketone (PEEK) material using 3D printing technology were determined. Two populations of specimens were investigated, the first of which contained an amorphous structure, while the other held a crystal structure. The studies also investigated the influence of the print directionality on the mechanical properties obtained. Static tensile, three-point bending, and impact tests were carried out. The results for the effect of the structure type on the tensile properties showed that the modulus of elasticity was approximately 20% higher for the crystal than for the amorphous PEEK form. The Poisson's ratios were similar, but the ratio was slightly higher for the amorphous samples than the crystalline ones. Furthermore, the studies included a chemical PEEK modification to increase the hydrophilicity. For this purpose, nitrite and hydroxyl groups were introduced into the chain by chemical reactions. The results demonstrate that the modified PEEK specimens had worse thermoplastic properties than the unmodified specimens.