A new metal–organic coordination polymer [Zn₂(sedc)₂(dabco)] (1se; sedc²⁻ = selepophene-2,5-dicarboxylate; dabco = 1,4-diazabicyclo[2.2.2]octane) was synthesized and characterized by single-crystal X-ray diffraction analysis. This MOF is based on {Zn₂(OOCR)₄N₂} paddle wheels and is isoreticular to the family of [Zn₂(bdc)₂(dabco)] derivatives (1b; bdc²⁻ = 1,4-benzenedicarboxylate) with pcu topology. The gas adsorption measurements revealed that 1se shows a 15% higher CO₂ volumetric uptake at 273 K and 28% higher CO₂ uptake at 298 K (both at 1 bar) compared to the prototypic framework 1b. Methane and nitrogen adsorption at 273 K was also investigated, and IAST calculations demonstrated a pronounced increase in CO₂/CH₄ and CO₂/N₂ selectivity for 1se, compared with 1b. For example, the selectivity factor for the equimolar CO₂/CH₄ gas mixture at 1 bar = 15.1 for 1se and 11.9 for 1b. The obtained results show a remarkable effect of the presence of selenium atom on the carbon dioxide affinity in the isoreticular metal–organic frameworks with very similar geometry and porosity.

Three isostructural metal–organic frameworks ([Ln₂(phen)₂(NO₃)₂(chdc)₂]·2DMF (Ln³⁺ = Y³⁺ for 1, Eu³⁺ for 2 or Tb³⁺ for 3; phen = 1,10-phenanthroline; H₂chdc = trans-1,4-cyclohexanedicarboxylic acid) were synthesized and characterized. The compounds are based on a binuclear block {M₂(phen)₂(NO₃)₂(OOCR)₄} assembled into a two-dime nsional square-grid network containing tetragonal channels with 26% total solvent-accessible volume. Yttrium (1)-, europium (2)- and terbium (3)-based structures emit in the blue, red and green regions, respectively, representing the basic colors of the standard RGB matrix. A doping of Eu³⁺ and/or Tb³⁺ centers into the Y³⁺-based phase led to mixed-metal compositions with tunable emission color and high quantum yields (QY) up to 84%. The bright luminescence of a suspension of microcrystalline 3 in DMF (QY = 78%) is effectively quenched by diluted cinnamaldehyde (cinnamal) solutions at millimolar concentrations, suggesting a convenient and analytically viable sensing method for this important chemical.

The paper presents the results of studies of the composition of secondary Fe, Pb, Cu minerals, formed in contrasting physico-chemical conditions of the stockpiled tailings from the enrichment of Salair barite-polymetallic ores (West Siberia, Russia). The complex mineral composition of ores containing pyrite, chalcopyrite, sphalerite, galena, fahlore, and long-term chemical weathering contributed to the formation of monomineral and zonal secondary rims and fillings of the intergranular space, which were identified using modern research methods. Plumbojarosite, anglesite, cerussite, and iron hydroxides are predominant among them; pyromorphite, hinsdalite, and covellite are less abundant. Thermodynamic modeling was used to solve the inverse problem of restoring the composition of solutions that led to a sequence change in associations of secondary minerals. The observed processes are determined not only by chemical interaction, but also by electrochemical reactions in the systems under consideration, where various mineral components act as galvanic couples. These two processes, combined with the physicochemical parameters of the environment (pH, Eh, ionic composition of solutions), lead to stepwise or incomplete oxidation of the original minerals, followed by selective deposition of the secondary compounds.

Relevance. The need to understand the features of chemical weathering processes of man-made bodies that directly supply large amounts of toxic elements to the environment and affect the quality of water, air, and soils in cities and towns where stored waste is located. Aim. To determine the composition of the interpore fluid with the calculation of the chemical forms of the elements using physico-chemical modeling. Methods. XRF, XRF-SI, ICP-MS, capillary electrophoresis, stepwise leaching, thermodynamic modeling. The Visual Minteq 3.0 program was used for geochemical modeling of the forms of elements in solutions. Results and conclusions. The authors have carried out the studies on the example of the site of the old sulfide-containing Talmovskie Peski tailings dam (Salair, Kemerovo region). In the dam easily soluble salts are washed away by seasonal flows, leaching solutions flow into low relief areas with the formation of temporary reservoirs and puddles, their stagnation, transformation of physico-chemical conditions, deposition of intermediate compounds and then migration of drainage of already modified composition into the river network. The composition of water extracts from different horizons of the tailing dump showed that upon contact with seasonal flows, metals pass into solution in the form of aqua ions and sulfate complexes. This immediately allows you to divide them into several migration groups. The main element dictating the conditions is iron. It forms hydroxide complexes. This leads to the precipitation of amorphous Fe(OH)3 compounds already at pH>3.5, the deposition of abundant ochres, an increase in the acidity of waters, and a sharp increase in dissolved forms of elements. All this ultimately serves as a source of hydrochemical anomalies in the Malaya Talmovaya River, where runoff from the tailings dam enters. For citation: Korneeva T.V., Saeva O.P., Bortnikova S.B., Gaskova O.L., Volynkin S.S. Geochemical anomalies of mobile forms of elements in the pore space of technogenic bodies. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2026, vol. 337, no. 5, pp. 187-202. https://doi.org/10.18799/24131830/2026/5/4954