X-ray absorption spectroscopy measurements were used to determine the structure of the first coordination shell of Fe(II) ions in aqueous and acetone based solutions. Extended X-ray absorption fine structure analysis coupled with ab initio X-ray absorption near edge structure calculations confirms the octahedral coordination of the iron ion in water based solution. Data collected for acetone rich solutions can be reproduced assuming coexistence of the octahedral Fe(H(2)O)(6)(2+) and tetrahedral [FeCl(4)](2-) complexes. Distortion of the tetrahedral coordination of ion was detected in some of the acetone based solutions.

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Six point generalization of the van der Pauw method is presented. The method is applicable for two dimensional homogeneous systems with an isolated hole. A single measurement performed on the contacts located arbitrarily on the sample edge allows to determine the specific resistivity and a dimensionless parameter related to the hole, known as the Riemann modulus. The parameter is invariant under conformal mappings of the sample shape. The hole can be regarded as a high resistivity defect. Therefore the method can be applied for experimental determination of the sample inhomogeneity.

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The results of magnetic properties of ThFexAl12–x powder samples with iron concentration x = 4, 4.5 and 5, studied by means of X‐ray (XD) and neutron diffraction (ND) techniques as well as the Mössbauer spectroscopy with the monochromatic circularly polarised source (MCPMS), and magnetisation measurements using vibrating sample magnetometer (VSM) are presented. Unpolarized neutron diffraction pattern leaves no doubts that the modulated magnetic structure is observed in the tetragonal ThFe4Al8 compound. The interpretation of our neutron data requires the presence of non‐zero magnetic propagation vectors different from the nuclear one. ThFe4Al8 sample has double spiral structure with moments rotating in a plane perpendicular to the wave vector as well as to . Both of them are temperature independent in the range 1.5 K–70 K. The value of iron magnetic moment is close to 1 μB/Fe atom at 1.5 K.