The novel Cr_1-xTi_xSecompounds have been synthesized for x = 0, 0.05, 0.10 and 0.15. Although bothCrSe and TiSe are individually reported as nickel arsenide (NiAs) structuretype phases [1, 2], solid solutions in this system have not been previouslysinthesized. Inspired by a similar system containing vanadium instead oftitanium [3], we set to discover new related solid solutions. The mentionedcompounds were synthesized by heating stoichiometric mixtures of the pureelements inside evacuated quartz ampoules at different times and temperaturesdepending on composition. Structural characterization was made using Powder X-RayDiffraction data. All samples belong to the P6₃/mmc space group andshare a NiAs-type structure, with slight changes on cell parameters for eachcomposition (from a = 3.684 Å and c = 6.024 Å for CrSe to a = 3.668 Å and c = 6.040Å for Cr_0.85Ti_0.15Se). Chromium andtitanium are known to have different oxidation states in selenide compounds,both varying between +2 and +4. X-ray Emission Spectroscopy (XES) measurementswere carried out in order to study the oxidation state of chromium in these newcompounds. By comparing peak positions in high-resolution Kβ XES spectra ofchromium selenides and the corresponding peaks in appropriate standards,oxidation states can be inferred for each sample [4]. All three substitutedsamples contain chromium in an average +1.9 ± 0.2 oxidation state. Additionalphysical characterization includes resistivity measurements carried out between80 and 300 K. Samples show a metallic behaviour respect to temperature change. Theresults of these measurements indicate an overall decrease in resistivity withthe addition of titanium in comparison with CrSe. These results and itsconclusions will be further discussed. In conclusion, we were able to obtain thedesired solid solutions. All samples belong to the expected space group andshare a structure type. Oxidation states were assessed by XES and resistivitymeasurements were performed and analysed. Further studies are required tocontinue probing the properties of these new solid solutions.

1.      V. H. Haraldsen, Kowalski E. ?Das magnetische Verhalten der Chalkogenidedes zweiwertigen Chroms? Z. Anorg. Chem 224 (1935) 329-336

2.      P. Ehrlich ?X-Ray Investigation of Titanium Sulfides and Vanadium Monotelluride?Z. Anorg. Chem 260 (1949) 13-13.

3.      S.Yuri, Ohta S. et al. ?Magnetic susceptibility, electrical resistivity and thermal expansioncoefficient of NiAs-type V_1-xCr_xSe? J. Magn. Magn. Mater. 70 (1987) 215-217.

4.       M. Torres Deluigi, Tirao G. et al. ?Dependence with theoxidation state of X-ray transition energies, intensities and natural linewidths of CrKβ spectra?, Chem. Phys. 325 (2006)477-484.