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In the paper, a procedure was suggested for making plant oil blends of desirable physico-chemical and performance parameters. There was applied a rule of additivity of parameters of component oils in the blend to get oil products with modified nutritional characteristics. The other objective of the research study was to test the usefulness of the procedure when projecting thermal properties of the blends for deep frying. To make oil blends, plant oils were used that were produced by Oleofarm Ltd. The oil blends were analysed using chromatographic and spectroscopic methods. Their chemical parameters constituted an input dataset to make blends of expected performance properties. It was shown experimentally that it was possible to theoretically project physico-chemical and thermal parameters of the final oil blend. When knowing the chemical parameters of individual blend-forming oils, it is possible to employ them to determine the parameters of the final blend. There were suggested oil compositions for the preparation of advantageous blends to be used for deep frying and salad dressings. Thus there was confirmed the purposefulness of blending the oils in order to make a product the qualities of which could be geared to the specific utility purposes.

Coordination polymers with multiple non-centrosymmetric phases have sparked substantial research efforts in the materials community. We report the synthesis and properties of a hitherto unknown cadmium dicyanamide coordination polymer comprising benzyltrimethylammonium cations (BeTriMe+). The room-temperature (RT) crystal structure of [BeTriMe][Cd(N(CN)2)3] (BeTriMeCd) is composed of Cd centers linked together by triple dca-bridges to form one-dimensional chains with BeTriMe+ cations located in void spaces between the chains. The structure is polar, the space group is Cmc21, and the spontaneous polarization in the c-direction is induced by an arrangement of BeTriMe+ dipoles. BeTriMeCd undergoes a second-order phase transition (PT) at T1 = 268 K to a monoclinic polar phase P21. Much more drastic structural changes occur at the first-order PT observed in DSC at T2 = 391 K. Raman data prove that the PT at T2 leads to extensive rearrangement of the Cd-dca coordination sphere and pronounced disorder of both dca and BeTriMe+. On cooling, the HT polymorph transforms at T3 = 266 K to another phase of unknown symmetry. Temperature-resolved second harmonic generation (TR-SHG) studies at 800 nm confirm the structural non-centrosymmetry of all the phases detected. Optical studies indicate that BeTriMeCd exhibits at low temperatures an intense emission under 266 nm excitation. Strong temperature dependence of both one-photon excited luminescence and SHG response allowed for the demonstration of two disparate modes of optical thermometry for a single material. One is the classic ratiometric luminescence thermometry employing linear excitation in the ultraviolet region while the other is single-band SHG thermometry, a thus far unprecedented subtype of nonlinear optical thermometry. Thus, BeTriMeCd is a rare example of a dicyanamide framework exhibiting polar order, SHG activity, photoluminescence properties and linear and nonlinear optical temperature sensing capability.

KMeY(PO4)2:5% Eu3+ phosphates have been synthesized by a novel hydrothermal method. Spectroscopic, structural, and morphological properties of the obtained samples were investigated by X-ray, TEM, Raman, infrared, absorption, and luminescence studies. The microscopic analysis of the obtained samples showed that the mean diameter of synthesized crystals was about 15 nm. The KCaY(PO4)2 and KSrY(PO4)2 compounds were isostructural and they crystallized in a rhabdophane-type hexagonal structure with the unit-cell parameters a = b ≈ 6.90 Å, c ≈ 6.34 Å, and a = b ≈ 7.00 Å, c ≈ 6.42 Å for the Ca and Sr compound, respectively. Spectroscopic investigations showed intense 5D0 → 7F4 transitions connected with D2 site symmetry of Eu3+ ions. Furthermore, for the sample annealed at 500 °C, europium ions were located in two optical sites, on the surface of grains and in the bulk. Thermal treatment of powders at high temperature provided better grain crystallinity and only one position of dopant in the crystalline structure. The most intense emission was possessed by the KSrY(PO4)2:5% Eu3+ sample calcinated at 500 °C.

Linum usitatissimum L. is a plant used by human since ancient times. Presently flax has both industrial and nutritional significance. The programmes of restoration of flax cultivation and processing are implemented to renew the importance of this plant for agriculture and economy. Genetic engineering methods and techniques of plant tissue cultures can answer this requirement, because they give the opportunity for obtaining of new plants and novel application of them. In the present study the impact of genetic modification of flax plants on the ability of morphogenesis was investigated. The subject of this research remain genetically modified flax plants enriched in poly-β-hydroxybutyrate (PHB), interesting biodegradable compound showing bioactive properties and acting as anti-inflammatory and anti-microbial factor. Another aim of this study was to characterize chemical and structural properties of callus derived from the engineered plants in comparison to the data obtained for non-transgenic, control callus cultures. The presence of PHB was confirmed by FTIR technique and it was suggested that this polymer may have impact on about 20% higher biomass growth observed for transgenic callus cultures in comparison to control cultures. The level of phenolic compounds was not significantly changed in the transgenic calluses when compared to wild-type cultures. The extracellular matrix (EMC) was noticed for the surface of genetically modified calluses, such structure was not visible for calluses derived from the control cultures. The cellulose in plant cell walls of transgenic calluses was structurally changed, it was not as organized as in control callus, resulting in lower crystallinity index values.

Two neodymium(III) six-coordinate complexes NdCl3(3-Br-4-CH3OC7H7NO)3 (Nd1) and Nd(C7H9NO)5(C4H8O2)(ClO4)3 (Nd2) have been synthesized and characterized. The FT-IR and FT-Raman data were acquired, and a complete vibrational assignment of the fundamental modes of the compounds was carried out. The frequencies calculated for the both ligands and scaled using the B3LYP approach with the 6-311G(2d,2p) basis set correspond very well to the experimental values. The XRD results, IR and Raman spectra were discussed in terms of a possible structure and composition of the studied compounds. The optical absorption and emission spectra were investigated at room temperature. The emission decay is mono exponential indicating that the energy transfer from the ligand occurs straight to the 4F3/2 level. The lifetime of this level is about 2.5 μs? A possibility of the energy transfer between the ligands under study and neodymium ions was considered. The calculations of the spin Hamiltonian parameters and EPR data simulation were performed using the electron paramagnetic resonance and nuclear magnetic resonance (EPR-NMR) program.

The crystal and molecular structure and physicochemical properties of 2-N-methylamino-3-methylpyridine N-oxide (MA3MPO) have been studied. MA3MPO was synthesized from 2-amino-3-methylpyridine by several steps to form colorless crystals suitable for crystallographic analysis. The data reveal that MA3MPO crystallizes in the monoclinic space group P21/n. The studied compound contains a nearly flat triply substituted pyridine skeleton whose structure is stabilized by an intramolecular N–H⋅⋅⋅O hydrogen bond. The N-oxide molecules are connected together by weak C–H⋯O hydrogen bonds, an acceptor of which is the oxygen atom from the N-oxide group. This leads to creation of two-dimensional network of hydrogen bonds. Its IR, Raman, UV–Vis and luminescence spectra have been measured and analyzed on the basis of DFT and NBO quantum chemical calculations in which the B3LYP/6-311++G(d,p) approach was applied. The distribution of the electron levels in the studied compound has been analyzed in terms of the possibility of its participation in the ligand-to-lanthanide ion energy transfer., Graphical abstract Image 10178, Highlights • The 2-N-methylamino-3-methylpyridine N-oxide (MA3MPO) was synthesized and characterized. • The studied compound structure is stabilized by an intramolecular N–H⋯O hydrogen bond. • The molecules are connected together by weak C–H⋯O hydrogen bonds. • The amino group plays the role of effective hydrogen-bond donor but the N-oxide group is a hydrogen-bond acceptor. • X-ray, IR, Raman and DFT methods recognized the existence of the intramolecular N–H⋯O hydrogen bond in the studied compound.

We report density functional theory (DFT) studies of vibrational modes for benzyltrimethylammonium cations (BeTriMe+) as well as THz, IR and Raman studies of [BeTriMe][M(dca)3(H2O)] (dca = N(CN)2−, dicyanamide; M = Mn2+, Co2+, Ni2+) and their anhydrous analogues. These studies show that the anhydrous BeTriMeMn and BeTriMeNi have the same or very similar structures and loss of water molecules leads to significant changes in the metal-dicyanamide frameworks. In particular, the number of dca modes decreases, suggesting increase of crystal symmetry, probablly related with decrease in the number of non-equivalent dca bridges from two to one. Although it is possible that dehydration leads to a replacement of the coordinate Mn-O (Ni-O) bonds by Mn-N (Ni-N) bonds, wherein N atoms come from the C≡N groups of previously non-bridged dca units, reversibility of the dehydration process indicates that such new bonds are either not formed or are very weak. The anhydrous Mn and Ni compounds undergo similar reversible phase transitions to lower symmetry phases. The driving force for these transitions is most likely ordering of dca linkers but this process is accompanied by weak distortion of the metal-dicyanamide frameworks. In the case of BeTriMeCo, the loss of water molecules also leads to significant changes in the cobalt-dicyanamide framework. However, the structure of this analogue is different from the structures of the Mn and Ni counterparts, the number of unique dca linkers is preserved and the dehydration process is irreversible, suggesting more drastic rearrangement of the metal-dicynamide framework.

Potassium- and sodium-yttrium double tungstate nanopowders co-doped with Yb3+, Ho3+ ions were investigated for their magnetic properties for the first time. We performed the analysis of the compounds using two methods: Electron Paramagnetic Resonance (EPR) and static Magnetic Susceptibility (MS). We have described the symmetry of doped ions environment and corresponding magnetic, optical and structural properties of the above compounds obtained by hydrothermal and Pechini methods. It was performed for the compounds underwent to different calcination temperatures in the range from 600 °C to 800 °C. For potassium and sodium double tungstates the local symmetry of ytterbium ions is found to be C2 and does not change with the calcination temperature rise. Based on the finite-size effect we determined the relative size of the nanoparticles agglomeration, observing changes in the values of Curie-Weiss temperature and the intensity of the EPR signal for various calcination temperatures. The magnetic and structural properties of nanoparticles were compared to corresponding ones registered for single crystals and crystalline powders obtained using other methods.

In mammalian cells, 3-hydroxybutyrate (3-HB) is not only an intermediate metabolite during the oxidation of fatty acids, but also an important signaling molecule. On the other hand, the information about the metabolism or function of this compound in plants is scarce. In our study, we show for the first time that this compound naturally occurs in flax. The expression of bacterial &beta, ketothiolase in flax affects expression of endogenous genes of the 3-HB biosynthesis pathway and the compound content. The increase in 3-HB content in transgenic plants or after control plants treatment with 3-HB resulted in upregulation of genes involved in chromatin remodeling. The observation that 3-HB is an endogenous activator of methyltransferase 3 (CMT3), decreased DNA methylation I (DDM1), DEMETER DNA glycosylase (DME), and an inhibitor of sirtuin 1 (SRT1) provides an example of integration of different genes in chromatin remodeling. The changes in chromatin remodeling gene expression concomitant with those involved in phenolics and the lignin biosynthesis pathway suggest potential integration of secondary metabolic status with epigenetic changes.

The crystal and molecular structures of 4,4′-dimethyl-3,3′,5,5′-tetranitro-2,2′-hydrazobipyridine have been determined by X-ray diffraction studies and DFT quantum chemical calculations. The 6-311G (2d, 2p) basis set with the B3LYP functional has been used to discuss the optimised structure and vibrational dynamics of the studied compound. It crystallizes in the monoclinic C 2/ c space group with one-half molecule in the asymmetric unit. The intramolecular N H⋯O hydrogen bonds and weak intermolecular C H⋯O contacts play an important role in stabilization of the structure. Structural and vibrational properties of the studied compound have been compared to those of other similar compounds. The conformation of the hydrazo bridge has been analysed in relation to the intramolecular N H⋯O interactions inside the monomeric form. Low temperature behavior of the studied compound has been discussed.

Eu3+ complex with 1-(2,6-dihydroxyphenyl)ethanone in the solid state has been synthesized and characterized by elemental analysis, UV-visible, FT-IR and FT-Raman spectroscopies, powder X-ray diffraction, electron emission under femtosecond laser excitation. The stoichiometry and the formula of the studied complex have been proposed. Its physicochemical properties have been analyzed in terms of the structure and DFT calculations performed for the ligand. The luminescence and dynamics of the excited states depopulation have been studied using femtosecond laser excitation. Spectral and energetic transformation of femtosecond light impulses has been studied and possibility of the energy transfer between the ligand and the Eu3+ electron levels has been analyzed.

A solid state Eu3+ complex with dehydroacetic acid (DHA) has been synthesized and characterized by elemental analysis, UV–visible, FT-IR, FT-Raman, powder and single-crystal X-ray diffraction and optical spectroscopy studies. The complex has formula [Eu(DHA)2(H2O)5]NO3 with DHA = C8H7O4−, where the europium ions is in monocapped distorted square antiprism environment with coordination number nine. Its photophysical properties have been analyzed in terms of its molecular structure and DFT calculations performed for the representative crystal fragment including Eu3+ and two DHA ligands. The luminescence and dynamics of the excited states depopulation have been studied using femtosecond laser excitation. The energy transfer mechanism between the ligand and Eu3+ electronic energy levels has been proposed. The obtained results have been compared to those of Gd3+ dehydroacetic derivative.

The crystal structure of the all studied compounds was refined in the monoclinic C2/m ( C 2 h 3 ) space group. The IR and Raman spectra of polycrystalline AgRE(WO4)2 have been recorded and analysed using the factor group approach. In the theoretical considerations the C2/m, P2/c and C2/c unit cell structures were taken into account. The change of the unit cell parameters induced by the RE ions exchange has been analysed. The assignment of the observed bands to the internal and external modes has been proposed. The verification of the structure has been done on the basis of the vibrational behaviour of the studied tungstates. Absorption, emission and excitation spectra of the investigated AgRE(WO4)2 polycrystals have been measured and analysed. The luminescence decay times of 5D0 → 7F2 (Eu3+) and 5D4 → 7F5 (Tb3+) transitions have been calculated.

Four novel compounds, [NH3CH2CH2OH][MIIIMII(HCOO)6] with MIII = Fe and MII = Mn (HEAFeMn), MIII = Fe and MII = Ni (HEAFeNi), MIII = Cr and MII = Mn (HEACrMn) and MIII = Cr and MII = Co (HEACrCo), have been synthesized. They crystallize in the trigonal niccolite-type structure (space group P 3 ¯ 1c). Magnetic studies revealed that HEAFeNi, HEAFeMn and HEACrCo are weak ferromagnets with the ordering temperature of 43, 27 and 11 K, respectively, whereas HEACrMn does not order magnetically at least down to 2 K. A source of the ferromagnetic component is most likely a canting of the antiferromagnetically ordered moments by a small angle resulting from antisymmetric exchange or single-ion anisotropy. Raman and IR data confirm that all obtained samples are isostructural. Optical studies of HEACrMn show that local crystal field around Cr3+ ion is of intermediate strength with the Dq/B value of 2.57. Luminescence studies indicate that HEACrMn exhibits efficient Cr3+-based emission. Below 200 K, the 2E-4A2 phosphorescence observed as two bands at 686 and 696 nm becomes predominate.

Samples of lead and praseodymium tungstate solid solution were synthesized from the mixtures of PbWO4 and Pr2(WO4)3 tungstates with praseodymium concentration varied in a wide range. The IR and Raman spectra of polycrystalline Pb1-3x□xPr2xWO4 solid solution were recorded and analysed using the factor group approach, where x was changed from 0.0050 to 0.2222. In the theoretical considerations, the C4h cell symmetry was taken into account. The assignment of the observed bands to the internal and external modes was proposed. Absorption, emission and excitation spectra of the studied solid solutions were measured and analysed. The lifetime of the 3P0 and 1D2 multiplets for x = 0.0050 were measured to be 3.52 and 30.54 μs, respectively. The behaviour of luminescence upon femtosecond excitation was analysed.

This study is focused on the synthesis condition influence related to structural and spectroscopic properties of the potassium strontium pyrophosphate (K2SrP2O7) co-doped with Eu3+ and Eu2+ ions. The experimental parameters of the urea assisted combustion synthesis were optimized by temperature and time of calcination as well as reduction atmosphere composition. The obtained materials were structurally characterized using the X-Ray Powder Diffraction (XRPD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Spectroscopic properties were determined by emission spectra, excitation spectra, luminescence kinetics and luminescence temperature quenching measurements. It was found that increasing concentration of Eu3+ ions caused an increase of spectroscopic factors, which correspond to the relative integrated luminescence intensities of 5D0–7FJ transitions as well as structural defects. Moreover, the successful Eu2+ ion incorporation was proven by optical spectroscopic measurements, which showed the allowed f-d transitions.

The Ca4Nb2O9–xNd2O3 (where x = 0.1–1.0) pseudobinary samples were synthesized by the high-temperature solid state method. Optical properties of Nd3+ ions in this oxide system were studied and related to the structural phase transition dependent on the Nd2O3 oxide content. Structural and optical properties are discussed based on ATR IR, dielectric, diffuse reflectance and emission spectra measurements. The spectroscopic studies show a structural phase transition occurring for x = 0.5 and for which the initial limited solid solution transforms to the diphasic form of Ca2NdNbO6 and Nd2O3.

Silver phytate IP6, IP6Ag, IP6Ag2 and IP6Ag3 complexes in the solid state have been synthesized changing the phosphate to metal mole ratio. The obtained products have been characterized by means of chemical and spectroscopic studies. Attenuated total reflection Fourier transform infrared technique and Raman microscope were used in the measurements. These results were discussed in terms of DFT (Density Functional Theory) quantum chemical calculations using the B3LYP/6-31G(d,p) approach. The molecular structures of these compounds have been proposed on the basis of group theory and geometry optimization taking into account the shape and the number of the observed bands corresponding to the stretching and bending vibrations of the phosphate group and metal-oxygen polyhedron. The role of inter- and intra-hydrogen bonds in stabilization of the structure has been discussed. It was found that three types of hydrogen bonds appear in the studied compounds: terminal, and those engaged in the inter- and intra-molecular interactions. The Fermi resonance as a result of the strong intra-molecular O H⋯O hydrogen bonds was discovered. Electron absorption spectra have been measured to characterize the electron properties of the studied complexes and their local symmetry.

Attenuated total reflection Fourier transform infrared (ATR FT-IR) and confocal Raman microscopes were used to record horse fat depth profiles. The dependence of the unsaturation level and the iodi...

We report synthesis of two novel mixed-valence iron(II)-iron(III) formate frameworks templated by N-ethylmethylammonium (EtMeA+) and 2-Hydroxyethylammonium (HEA+) cations. X-ray diffraction shows that these compounds crystallize in the P 3 ¯ 1c niccolite-type structures. Optical studies confirm mixed-valence character of these compounds. Magnetic investigation reveals that both N-ethylmethylammonium iron formate (EtMeAFeFe) and 2-Hydroxyethylammonium iron formate (HEAFeFe) exhibit magnetic order at 36.5 and 37.0 K, respectively. EtMeAFeFe also exhibits large negative magnetization below 31.0 K indicating that this compound is an N-type ferrimagnet. We also present Raman and IR data for both compounds. In order to help assignment of modes corresponding to the EtMeA+ cation, we also performed quantum chemical calculations to derive the harmonic and anharmonic vibrational wavenumbers. The performed calculations revealed that protonation should affect most strongly modes related to vibrations of the N–H bonds as well as the stretching modes of the CH2 and CH3 groups attached to the N atom.

We report synthesis of four novel heterometallic MOFs, [(NH4)(H2O)][CrIIIMII(HCOO)6] with MII = Zn (NH4CrZn), Co (NH4CrCo), Mn (NH4CrMn) and Ni (NH4CrNi). X-ray diffraction shows that NH4CrZn crystallizes in the trigonal structure (space group P 3 ¯ 1c) with ordered Cr3+ and Zn2+ centers while NH4CrCo, NH4CrMn and NH4CrNi crystallize in the hexagonal system with chiral space group of P6322 and statistical occupation of the same sites by Cr3+ and M2+ ions. Raman and IR data confirm presence of water molecules and different confinement of the ammonium cations in the cavities of chiral and niccolite type metal formate frameworks. Optical studies show that Cr3+ ions in NH4CrZn and NH4CrMn are located at sites of strong crystal field with the Dq/B values of 2.54 and 2.47, respectively. Luminescence studies show that these compounds exhibit efficient Cr3+-based emission with the decay time of 8.1 μs (0.44 ms) at 295 K (10 K) for NH4CrMn and 8.3 μs (0.78 ms) for NH4CrZn.

The sub-solidus phase relation in the Ca4Nb2O9–Nd2O3 pseudo-binary system has been examined by X-ray powder diffraction (XRD), thermal analysis (DSC/TGA), IR, Raman and EPR spectroscopy. The results have shown that a limited solid solution of Nd2O3 in Ca4Nb2O9 with (Ca4Nb2)1-xNd2xO9-6x (0≤ x ​≤ ​0.5) formula and monoclinic structure of H–Ca4Nb2O9 is formed. The cell parameters of the solid solution linearly increase with increasing Nd2O3 content which is in accordance with the Vegard's law. The composition evolution of selected IR and Raman bands confirmed a change in short-range order for investigated ceramic solid solution. Temperature dependence of magnetic susceptibility and Curie-Weiss temperature for new solid solution were analyzed.

Na3Ln(PO4)2 orthophosphates (Ln = La, Gd) doped with Er3+ and co-doped with Cr3+ ions were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materials. They show that erbium and chromium ions substitute Ln3+ and also Na+ ions or Na+ channels forming complex EPR spectra. Both kinds of ions reveal ferromagnetic type of interaction which shows some anomaly at the temperature between 10 K and 15 K. Magnetic susceptibility reveals a weak antiferromagnetic kind of interaction dominating in the whole temperature range, from 3.5 to 300 K.

Eu 3+ complex with 2-hydroxy-4-metoxy-benzophenone (HMBP) in solid state has been synthesized and characterized by elemental analysis, UV–visible, FT-IR, FT-Raman spectroscopies, powder X-ray diffraction, electron emission excited by femtosecond pulses. The stoichiometry and formula of the studied complex have been proposed. Its physicochemical properties have been analyzed in terms of structure and DFT calculations performed for the ligand. The luminescence and dynamics of the excited states depopulation were studied using femtosecond laser excitation. The spectral and energetic transformation of femtosecond light pulses have been discussed and a possibility of an energy transfer between the singlet state of the ligand and the Eu 3+ electron levels has been considered.

The crystal and molecular structures of aquo 4,6-dimethyl- 5H -[1,2,3]triazolo[4,5- c ]pyridine in a zwitterionic form have been determined by X-ray diffraction and DFT quantum chemical calculations. The compound adopts a triclinic crystal structure, space group P-1 = C i 1 (No. 2) with Z = 2 and the unit cell parameters: a = 6.7452 A, b = 9.5292 A, c = 9.5554 A and α = 69.279°, β = 73.951°, γ = 74.242°. The temperature dependence of its IR and Raman spectra have been measured and discussed in terms of proton transfer dynamics. The molecular structure and simulated vibrational spectra of the studied compound have been determined using the DFT B3LYP/6-311G(2d,2p) approach. Vibrational characteristics of a triazolo-pyridinium system in the studied compound has been proposed. A role of water molecules in stabilization of the compound space structure has been considered.

The crystal and molecular structures of aquo 7-methyl-1H-[1,2,3]triazolo[4,5-c]pyridinium nitrate composite have been determined by X-ray diffraction and DFT quantum chemical calculations. The thermogravimetric and differential scanning calorimetric analyses were also performed. The compound crystallizes in a monoclinic structure, space group P21/n (No. 14) with Z = 4 and the unit cell parameters: a = 7.1392(3), b = 14.3163(5), c = 9.5900(4) and β = 107.330(4). The molecular structure and simulated vibrational spectra of the studied compound have been determined using B3LYP/6-311G(2d,2p) approach. The vibrational characteristics of the triazolo ring in the studied compound has been proposed. The role of the hydrogen bond in the formation of the salt composite has been discussed.

New europium and terbium [LnCl3L3(H2O)2] polycrystalline complexes were synthesized with the ligand L = 3-bromo-4-methylthio-2,6-lutidine N-oxide. IR, Raman, electron absorption UV-VIS and emission spectra measurements were carried out for these compounds. Re-crystallization of these materials led to formation of single crystals with another composition [LnL(H2O)7]Cl3∙L3, they were characterized by X-ray diffraction technique and spectroscopic measurements. Both types of the materials consist of eight coordinated LnCl3O3O’2 or LnOO’7 polyhedrons containing O - oxygen atoms of the N-oxide group, chlorine atoms or O’ - oxygen atoms of the water units. The crystal structure was solved for two complexes of the formula [Ln(L)(H2O)7]Cl3∙(L)3 where Ln = Eu and Tb. X-ray diffraction analysis reveals that these complexes are isostructural with P21/m space group. The optimization of the molecular system and frequency calculations were carried out using density functional theory (DFT). The DFT quantum chemical calculations of the vibrational wavenumbers were performed for the ligands used for the Eu3+ and Tb3+ ions complexation. The emission measurements were carried out with the femtosecond excitation. The effective ligand-to-metal energy transfer was discovered in the [LnCl3L3(H2O)2] complexes formed in the polycrystalline state.

Sodium-magnesium pentaphosphate with a formula Na 3 Mg 2 P 5 O 16 doped with europium(III) have been synthesized. The concentration of the rare earth ion activators was established to be 1 to 10 at.% in the doped samples. Spectroscopic and structural properties of the obtained samples were investigated by X-ray, Raman, infrared, absorption and luminescence studies. The structure of the studied material was confirmed as monoclinic P2/a = C 2h 4 (No. 13) similar to this described in the literature. The decay times were measured for all samples monitoring the maximum of emission at λ mon = 611 nm and exciting in the 5 L 6 band (λ exc = 396 nm). All decay curves were single exponential and lifetimes remain constant with value τ = 2 ms ± 0.2 ms for the all dopant concentration.

Room temperature FT-IR spectra in the range 30–4000 cm −1 and FT-Raman spectra in the range 80–4000 cm −1 of indium and lutetium MPX-type phthalocyanines have been compared. The assignment of the observed bands has been accomplished on the basis of DFT chemical calculations using the B3LYP functional and its long range corrected version - CAM-B3LYP. The calculations were carried out for the indium derivative using the LANL2DZ, CC-PVDZ basis sets, i.e. the following approximations were used: B3LYP/CC-PVDZ, B3LYP/CC-PVTZ, B3LYP/LANL2DZ, CAM-B3LYP/CC-PVDZ and CAM-B3LYP/LANL2DZ. The molecular structures of these derivatives have been discussed in terms of group theory and geometry optimisation taking into account the shape and number of the bands corresponding to the stretching and bending vibrations of MN 4 coordination polyhedron as well as the whole studied complex. The calculated structural parameters have been related to those from XRD studies. The usefulness of the proposed theoretical approaches in the prediction of the structural and vibrational data were analysed.

Thirteen edible oils: sunflower, avocado, hemp, high-linolenic flax, low-linolenic flax, safflower, walnut, roasted sesame, rice, corn, rapeseed, pumpkin seed, and hazel were studied in this work. Their fatty acid composition, iodine, acidic, peroxide, and saponification values were determined. Infrared and Raman spectra of the oils were recorded in the range 400–3200 cm−1. The integral intensities of the bands at about 1655 and 2852 cm−1 corresponding to ν(C=C) and ν(CH2) vibrations were evaluated and used to construct a relationship between the spectroscopic data and the iodine value. The following linear dependencies were obtained: Iν(C=C)/Iν(CH2) = 7.449 × 10−4 × iodine value – 0.0339 and Iν(C=C)/Iν(CH2) = 9.299 × 10−4 × iodine value – 0.023 for the infrared and Raman spectra with a correlation coefficient 0.988 and 0.976, respectively. These calibration lines can be used to determine the iodine value for oils with unknown unsaturation level, and may be applied for margarines and other fatty m...

Molecular structures of quercitin and quercitin sulfonic acid have been determined by DFT quantum chemical calculations. FT-IR and FT-Raman spectra have been measured in the solid state and discussed in terms of B3LYP/6-311G(2d,2p) approach. The role of the hydrogen bonds in stabilization of their structures has been analyzed. The IR spectra were measured in the temperature range 5–300 K and the observed effects were used in the discussion of the hydrogen bond behavior.

Two novel formate frameworks templated by ammonium and diethylammonium (DEtA+) cations have been synthesized. Chemical analysis as well as optical, Raman and IR studies showed partial substitution of nickel ions by Cr(III) or Fe(III). X-ray diffraction revealed that these compounds crystallize in the chiral-type structure of P6322 symmetry. The oxygen atoms from formate ligands form octahedral coordination around the metal centers and the octahedra are bridged by the formate groups in the anti-anti mode configuration forming the hexagonal structure with large channels expanding along the c direction. The channels are filled with disordered DEtA+ and NH4+ ions and they show unusual compression with the c/a ratio of only 0.862 and 0.852 for the iron- and chromium-containing compound, respectively. Magnetic studies revealed that the both compounds order magnetically at low temperatures but the ordering temperature is significantly higher for the iron compound (37 K) compared to the chromium analogue (26 K).

Syntheses of 5-nitro-2-(2-phenylhydrazinyl)pyridine (5-nitro-2-phenylhydrazopyridine), 3-methyl-5-nitro-2-(2-phenylhydrazinyl)pyridine (3-methyl-5-nitro-2-phenylhydrazopyridine), 4-methyl-5-nitro-2-(2-phenylhydrazinyl)pyridine (4-methyl-5-nitro-2-phenylhydrazopyridine) and 6-methyl-5-nitro-2-(2-phenylhydrazinyl)pyridine (6-methyl-5-nitro-2-phenylhydrazo-pyridine) have been described. Electronic absorption and emission spectra of the compounds in the solid state and in various solvents have been measured at room temperature and discussed in terms of DFT quantum chemical calculations. The molecular structures and energy sequences of the singlet and triplet states have been determined in the B3LYP/6-311G(2d,2p) approximations. The Mulliken analysis and non-bonding orbital approach have been used in characterization of the studied compounds. It has been shown that the HOMO-LUMO transition of the studied compounds is observed in the range 23,900 ÷ 29,300 cm −1 and in this excitation the π-electrons of phenyl ring are transferred to nitro group of pyridine ring. In such a transition the hydrazo-bridge should take part as a mediator. The luminescence of the studied hydrazo-compounds is weak, not measureable in the solid state but measureable in solution.

Time-dependent changes of chicken meat were studied using Fourier transform IR and Raman techniques. Small pieces of intact chicken breast muscle (pectoralis major) were used in the investigations. They were stored in air at 22 °C up to 10 days and their IR and Raman spectra were measured successfully. Analysis of the obtained spectra was performed using a deconvolution of the experimental bands into Lorentz components. All integral intensities of the observed bands were standardized using the statistical R2 coefficient of determination. The R2 values were automatically created as the output of the Origin software. The time-dependent changes of the spectra were used for meat spoilage detection. The analytical relationships between the integral intensities of selected bands have been derived indicating an increase of free amino acids content as the main effect of the chicken breast muscle spoilage.

New chemical compounds have been synthesized and their physicochemical properties have been characterized. N’-[2,4-dihydroxyphenyl) methylidene]-4-(4-fluorophenyl) piperazine-1-carbothiohydrazide, a novel semicarbazone has been obtained in the three stages of intermediate process and by the final crystallization from the methanol solution. The final and intermediate products have been studied using 1H, 13C NMR and MS spectroscopic techniques. The semicarbazone was applied as a ligand for the Tb3+ ion complexation and the obtained terbium compound has been characterized by elemental chemical analysis as well as by the IR, Raman, and electron absorption and emission techniques. Its molecular structure has been proposed. The probability of the ligand-to-metal energy transfer has been discussed.

Nanocrystalline MIY(WO4)2 double tungstates (MI = Li, Na, K and Rb) co-doped with Er3+ and Tm3+ ions were synthesized by hydrothermal and Pechini techniques and characterised by means of X-ray diffraction, infrared absorption and electron absorption spectra. Their emission spectra and luminescence decay kinetics were recorded at ambient temperature. These investigations were focused on impact of structural changes and morphology inducing by the alkaline ion on the Er ↔ Tm energy transfer efficiency in the studied nanocrystalline oxide systems. The effect of the thermal treatment on morphology and spectroscopic properties of the synthesized nano-materials was studied. Furthermore, emission spectra attained under different excitation as well as study on luminescence decay curves made it possible to determine the differences and dynamics of feeding and relaxation of excited states involved in luminescence phenomena. The energy transfer mechanism between Er3+ and Tm3+ ions was proposed and analysed in terms its usefulness in the phosphors and optical amplifiers operating at 1.8 μm.

[Ln2(2-hydroxy-5-methyl-nicotinic acid)6(H2O)4] and Ln2(5-methyl-nicotinic acid)6(H2O)4] complexes (Ln = Gd, Tb) have been synthesized and characterized by means of powder X-ray diffraction, IR, Raman, electron UV–Vis and emission measurements. The luminescence and dynamics of the excited states depopulation have been studied using femtosecond laser excitation. The singlet and triplet states of nicotinic acid were localized using DFT quantum chemical calculations. The energy transfer mechanism between the electron levels of the ligands and Tb3+ ion have been proposed.

The lanthanide [Ln(QSA)3(H2O)](H2O)5 complexes in the polycrystalline state and embedded in the silica glass, where Ln = La, Pr, Nd, Eu, Sm, Dy, Er, Gd, Ho, Tb, were studied and characterized using spectroscopic methods. The europium complex was additionally studied theoretically based on the DFT approach which provided molecular structure and electron transition assignment. The emission spectra measured at 293 and 77 K proved the transformation of excitation pulses into the phonon energy. The EPR studies of the Er, Gd, Dy and Sm derivatives were used to determine spin Hamiltonian parameters and g – components. The antiferromagnetic interactions were found and the local monoclinic symmetry of the coordination polyhedron was proposed.