•Laser method for synthesis of bimetallic materials for enzyme-free microbiosensors.•Relationship between the structure of complexes and the properties of microbiosensors is shown.•The gap in ...knowledge about the structure of bimetal wine complexes has been filled.
The use of laser methods for synthesizing new materials for non-enzymatic electrochemical microsensors for express analysis of biological fluids is a promising scientific question.
Laser-induced chemical liquid phase deposition is the laser deposition of invisible miniature bimetallic deposits from aqueous solutions of salts and complexes of transition metals. Bimetallic complexes containing two transition metal cations in the shell of one ligand are of increased interest. There is an information gap in this area even for ligands such as tartrate. The studies carried out make it possible to obtain new information on the structure of bimetallic tartaric complexes in solutions containing simultaneously copper, nickel, silver, iron, and cobalt.
A new derivative of acridine, 4,5-bis(N,N-di(2-hydroxyethyl)iminomethyl)acridine (BHIA), which is a selective fluorophore relative to cadmium cations, is studied by the method of surface-enhanced ...Raman scattering (SERS). The SERS spectra of BHIA adsorbed on colloidal silver particles exhibit a high intensity and temporal stability of the signal. An assignment of the bands present in the studied spectral range is given. The dependence of the SERS spectra of BHIA on the solution’s pH reveals that the ligand can exist on the surface in protonated and deprotonated forms. The stability of the deprotonated form on the surface suggests that the ligand interacts with the surface by means of a conjugated π-system of aromatic rings. The addition of the salt of halide ions to the solution has a significant influence on the SERS spectrum. This effect is due to the displacement of the adsorbate molecules from the first monolayer, which is accompanied by the transition of BHIA from the chemi- to the physisorbed form.
The IR spectra of aqueous solutions of MClO
4
, MNO
3
, MCl (M = Li, Na), CsCl, and Na
2
SO
4
were measured at frequencies of 5400–7500 cm
−1
over a wide concentration range from 0.12 M up to ...saturation concentrations at 25°C. Chemometric analysis of the experimental data matrix was performed. Regularity was detected in distribution of the IR spectra of the studied aqueous solutions on the the plot of analysis scores by the principal component method depending on the nature of the anion-water interaction. The influence of the nature of the salt anion and cation on the water structure in aqueous electrolyte solutions was demonstrated. The existence and interconversion of the spectral forms of water with changing electrolyte concentration in solution were revealed.
The state of water in aqueous solutions of group IIIA metal perchlorates at 25°C was studied by the IR spectroscopy in the range of 5400–7500 cm
−1
. The optical density values of the solution ...measured at different wavelengths were combined in a matrix of experimental data of the uniform dimension. The matrices were chemometrically analyzed. A number, spectra, and concentration profiles of the spectral forms existing in the solution were determined. By the principal component method, the IR spectra of the studied systems are grouped into the mathematical clusters according to the nature of the cation-water interaction in the solution. The combined use of the infrared spectroscopy and chemometric analysis showed that the structural changes in the solution predicted by the generalized phenomenological model are due to the existence and interconversion of the spectral forms.
Freezing points of solutions M(ClO
4
)
3
-H
2
O (M = Sc, Y, La) of different concentrations were determined. The solubility polytherms of the perchlorate systems studied, as well as aluminum, ...gallium, and indium perchlorates were compared with the concentration dependences of different properties of the corresponding solutions. Viscometry and IR spectroscopy allowed the special points on these dependences to be correlated with eutectic concentrations. Structural changes in the systems studied as a function of solute concentration were described.
New complexes of 4,5-bis(N,N-di(2-hydroxyethyl)iminomethyl)acridine have been prepared and studied by using techniques including X-ray single crystal, IR and Raman spectroscopy. The three different ...coordination manners of the molecule were found depending on metal cation and anion. Display omitted
Five new 1:1 metal complexes of highly selective acridine-based fluorophore 4,5-bis(N,N-di(2-hydroxyethyl)iminomethyl)acridine (BHIA) with Ag(I), Cu(II) and Cd(II) were synthesized, characterized and investigated by the methods of single crystal X-ray diffraction, IR, and Raman spectroscopy. Single crystal X-ray analysis reveals that three different coordination manners of the BHIA occur. Five atoms of the BHIA molecule take part in the formation of complex with Ag(I) and six atoms are involved in the formation of complex with Cu(II). In the case of BHIA with Cd(II) interaction, the coordination possibilities of the cation depend on an anion and vary from five to seven. The investigation of BHIA complexes by IR and Raman spectroscopy shows that if there are two free hydroxyl groups in the molecule then the vibrational spectrum arises from many rotational conformations. The different binding manner of BHIA molecule with metal cations is the most clearly manifested in the IR spectrum in the region of the stretching OH-vibrations.
•Intermolecular H-bonds in the BHIA crystal are the cause of the molecular symmetry distortion.•BHIA IR spectra assignment indicates the bands of vibrations with the considerable participation of ...chelate fragment atoms.•BHIA Raman spectrum is formed mainly from the aromatic fragment fundamental modes.
A new acridine derivative, 4,5-bis(N,N-di(2-hydroxyethyl)iminomethyl)acridine (BHIA), having high selective characteristics of the quantum fluorescence yield towards cadmium cations is studied in this work by X-ray single crystal and vibrational spectroscopy methods. X-ray single crystal analysis revealed that aliphatic substitutes joined to the acridine fragment in BHIA molecule are asymmetric. Non-equivalence of their hydroxyethyl groups occurs due to formation of intermolecular hydrogen bonds. To carry out the assignment of IR and Raman spectra of BHIA the calculations of optimized geometries and vibrational spectra are made on the basis of the density functional theory (DFT). The calculated geometrical parameters and vibrational spectra are in agreement with the experimental data. The assignment performed for 400–1800cm−1 region shows that the vibrations from all fragments of BHIA molecule are presented in the IR spectrum while the vibrations with only main contribution of acridine fragment are observed in the Raman spectrum. Based on the analysis of the normal vibrations forms the most sensitive to complexation bands in the IR spectrum are predicted.
Crystal structures of isomorphous crystal nonahydrates of aluminum, gallium, and scandium perchlorates were determined by the X-ray crystal analysis at room temperature. The estimate of associates ...present in concentrated solutions was carried out by the method of X-ray diffraction in aqueous solutions of aluminum perchlorate.
Solubility polytherms of the system M(ClO
4
)
3
-H
2
O (M
3+
= Al
3+
, Ga
3+
, In
3+
) were measured. Positions of singular points and vitrification ranges were determined. Values of eutectic ...concentrations were compared with earlier known data on the inversion concentrations measured by the viscometry method. Compositions of found crystalline hydrates were calculated from the solubility polytherms. The concept of the ability of the studied aqua cations to show properties of aqua acids, of the structure of solutions of posteutectic concentrations (structurally forced processes and microheterogeneity), of the electronic structure of M
3+
cations, and of the localized hydrolysis phenomenon were used to understand the existence of the polyaqua compounds.
IR spectra of propylene glycol solutions in water were measured in the region of the first overtone of water. The inhibition efficiency of calcium sulfate was determined as a function of the pH value ...and propylene glycol content of water. A concept is suggested for taking into account the water-complexone interaction in inhibition of calcium sulfate crystallization with phosphonic acids.
