Ferroelectric, Switchable Dielectric and Nonlinear Optical Properties in Inorganic-Organic Lead-Free 1D Hybrids Based on Bi(III) and Azetidine: (CNH)[BiCl], (CNH)[BiBr].

This study investigates lead-free organic-inorganic hybrids (CNH)[BiCl] () and (CNH)[BiBr] (), focusing on their structural, dielectric, ferroelectric, and optical properties. Both compounds exhibit paraelectric () to ferroelectric () phase transitions (PTs) at 230/233 K and 228/229 K, respectively, transitioning from orthorhombic () to monoclinic (2) phases, with distorted [BiX] octahedra forming 1D chains. Quasielastic neutron scattering and solid-state H NMR studies reveal the localized motion of azetidinium cations.

Progressive Structural Complexity in Ferroelectric 1,2,4-Triazolium Hexabromoantimonate(III): Interplay of "Order-Disorder" and "Displacive" Contributions to the Structural Phase Transitions.

Halobismuthates(III) and haloantimonates(III) with the RMX chemical composition create a new and broadly unexplored class of ferroelectric compounds. In this paper, we report the haloantimonate(III) ferroelectric comprising an aromatic (1,2,4-triazolium) cation, i.e.

Dielectric-Optical Switches: Photoluminescent, EPR, and Magnetic Studies on Organic-Inorganic Hybrid (azetidinium)MnBr.

A new organic-inorganic hybrid, , has been synthesized and characterized. The thermal differential scanning calorimetry, differential thermal analysis, and thermogravimetric analyses indicate one structural phase transition (PT) at 346 and 349 K, on cooling and heating, respectively. crystallizes at 365 K in the orthorhombic, , structure, which transforms to monoclinic 2/ at 200 K.

Analysis of charge density in nonaaquagadolinium(III) trifluoromethanesulfonate - insight into Gd-OH bonding.

The experimental charge-density distribution in [Gd(HO)](CFSO) has been analysed and compared with the theoretical density functional theory calculations. Although the Gd-OH bonds are mainly ionic, a covalent contribution is detectable when inspecting both the topological parameters of these bonds and the natural bond orbital results. This contribution originates from small electron transfer from the lone pairs of oxygen atoms to empty 5d and 6s spin orbitals of Gd.

Phase transition tuning by Fe(iii)/Co(iii) substitution in switchable cyano-bridged perovskites: (CHN)[KFeCo(CN)].

The single-crystals of mixed (CHN)[KFeCo(CN)] crystals, with different ratios of x = 0, 0.29, 0.42, 0.

Structural and thermodynamic aspects of hydration of Gd(iii) systems.

X-ray crystal structures of Gd(iii) and Lu(iii) aqua ions as well as their complexes with polyaminopolycarboxylates (EDTA, CDTA, EGTA, DTPA, DOTA) were determined: [Gd(H2O)9](CF3SO3)3, [Gd(H2O)8]Cl3·C10H20O5, [Lu(H2O)8]Cl3·C12H24O6·4H2O, [C(NH2)3][Gd(EDTA)(H2O)3], [C(NH2)3]2[Lu(EDTA)(H2O)2]ClO4·6H2O, [C(NH2)3][Lu(CDTA)(H2O)2]·6H2O, [C(NH2)3][Gd(EGTA)(H2O)]·2H2O, [C(NH2)2(N2H4)][Gd(HDTPA)(H2O)]·2H2O, Na[Gd(DOTA)(H2O)]·4H2O, and K2[Lu(DOTA)]Cl·4.6H2O. The weighted sums of UV absorption spectra of appropriate crystals were used to reproduce the spectra of the Gd(iii) aqueous solutions in the temperature range 276-363 K.

Unraveling the Ground State and Excited State Structures and Dynamics of Hydrated Ce Ions by Experiment and Theory.

The 4f-5d transition of Ce provides favorable optical spectroscopic properties such as high sensitivity and quantum yield, making it a most important dopant for lanthanide-activated phosphors. A key for the design of these materials with fine-tuned color emission is a fundamental understanding of the Ce ground state and excited state structures and the dynamics of energy transfer. Such data is also crucial for deriving coordination chemistry information on Ce ions in different chemical environments directly from their optical spectra.

Eu(iii) and Cm(iii) tetracarbonates - in the quest for the limiting species in solution.

The structural and spectroscopic properties of the compounds [C(NH)][Gd:M(CO)(HO)]·0.75HO (1) and [C(NH)][Y:M(CO)]·2HO (2) (M = Eu, Cm) were determined. The crystals contain differently hydrated tetracarbonate complexes, [M(CO)(HO)] and [M(CO)], which were used as structural and spectroscopic models of Eu(iii) and Cm(iii) tetracarbonate species in aqueous solutions.

The first example of ab initio calculations of f-f transitions for the case of [Eu(DOTP)] complex-experiment versus theory.

Crystal structures and photophysical properties (IR and UV-vis-NIR) of two compounds, [C(NH)][Eu(DOTP)]·12.5HO and K[Eu(DOTP)]·11HO (DOTP = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrakis (methylenephosphonic acid)), were determined. The DOTP ligand is bonded to Euvia four O and four N atoms, filling thus eight coordination sites of Eu.

A new approach to determination of hydration equilibria constants for the case of [Er(EDTA)(H2O)(n)](-) complexes.

Two anionic complexes [Er(EDTA)(H2O)2](-) and [Er(EDTA)(H2O)3](-) were obtained in the form of the following compounds: [C(NH2)3]2[Er(EDTA)(H2O)2]ClO4·6H2O () and Na[Er(EDTA)(H2O)3]·5H2O (), respectively. The UV-vis-NIR absorption spectra of both monocrystals were measured at room temperature and at 4.2 K.

Charge density distribution in aminomethylphosphonic acid.

The experimental charge density distribution in aminomethylphosphonic acid has been determined from X-ray diffraction and its topological features have been analyzed. The results have shown that the P-O bonds are highly polarized, moreover the P-OH bond is weaker than the bonds to unprotonated O atoms. These facts have been confirmed by theoretical density functional theory (DFT) calculations, which have shown that the single, strongly polarized bonds within the phosphonate group are modified by hyperconjugation effects.

[Tobacco smoking influence on the level of sex hormones--animal model].

Numerous studies warn that women who smoke can suffer from weakened functioning of their ovaries and disturbed synthesis and metabolism of hormones. This may cause many pregnancy complications or premature menopause and osteoporosis. Moreover, smoking disturbs the menstrual cycle, decreases the effectiveness and increases the undesirable effects of the hormone replacement therapy.

From structural properties of the EuIII complex with ethylenediaminetetra(methylenephosphonic acid) (H8EDTMP) towards biomedical applications.

Crystals of Eu(III) with ethylenediaminetetra(methylenephosphonic acid) (H(8)EDTMP) and with ethylenediaminetetraacetic acid (H(4)EDTA) have been synthesized in the same experimental conditions and their X-ray analyses have been performed. The EDTMP ligand wraps the Eu(III) ion in a fashion similar to its carboxylic analogue, EDTA, i.e.

Coordination ability of trans-cyclohexane-1,2-diamine-N,N,N',N'-tetrakis(methylenephosphonic acid) towards lanthanide(III) ions.

The proton and metal complex equilibria of trans-cyclohexane-1,2-diamine-N,N,N',N'-tetrakis(methylenephosphonic acid) (CDTP) with lanthanide(iii) ions, where Ln(III) = La(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III), Ho(III) and Lu(III) were studied. The stoichiometry, protonation and complex formation constants were determined by potentiometric titration at 25.0 degrees C and ionic strength of 0.