Zenneck-Sommerfeld type surface polaritons on the quartz crystal

The surface polariton (SP) propagation along the quartz crystal surface in the frequency region 1050–1090 cm^-1 was studied. The propagation length of SP rises from 50 to 105 μm when the frequencies goes down to transverse frequency (where SP is actually Zenneck-Sommerfeld type mode) and drastically decreases for lower frequencies.     

Structure,physicochemical properties,and reactivity of the [B<Subscript>9</Subscript>H<Subscript>9</Subscript>]<Superscript>2–</Superscript> anion

Data on the structure, properties, and reactivity of one of the least studied 3D aromatic clusters—nonahydro-closo-nonaborate anion [B₉H₉]^2–—have been systematized. It has been shown that the key aspects of its reactivity are related to structural flexibility, which essentially distinguishes the [B₉H₉]^2– anion from the higher representatives of closo-borate anions.     

Effect of the exposure time at recording an X-ray photoelectron spectrum on the charge state and environment of copper in mordenites

The effect of the exposure time at recording an X-ray photoelectron spectrum on the valence state and environment of copper in mordenite-type zeolite has been studied. It has been found that X-ray irradiation under the conditions of the experiment results in the redistribution of copper ions between the existing forms determined by differences in their coordination but without change in their valence state.     

Scattering of neutrinos (antineutrinos) on an electron with emission of a photon in the renormalizable theory of the weak and electromagnetic interaction

The differential and total cross sections are obtained for the processes \(v(\bar v) + e \to v(\bar v) + e + \gamma \) in the renormalizable theory of the weak and electromagnetic interaction.     

Effect of irradiation on siloxane block copolymers at doses below 100 kGy

A study of radiation-induced changes in polydimethylphenylsilsesquioxane block copolymers demonstrated that the impurities of dimethylcyclosiloxanes (D_x) that are formed in the synthesis of block copolymers disappeared at doses of 10–50 kGy. An increase in the dynamic viscosity (by a factor of 2–3) of 20: 5 and 20: 10 block copolymers irradiated at 50 kGy suggests that the formation of ≡Si-CH-CH₂-Si≡ bridges was not solely responsible for a structural rearrangement in the block copolymers. The rheological characteristics of the block copolymers changed under irradiation because of the transformations and interactions of D_x with the matrix.     

Synthesis and crystal structure of new double indium phosphates M 3 I In(PO4)2 (M I = K and Rb)

Double potassium indium and rubidium indium phosphates K₃In(PO₄)₂ (I) and Rb₃In(PO₄)₂ (II) are synthesized by solid-phase sintering at T = 900°C. The compounds prepared are characterized by X-ray powder diffraction (I and II), X-ray single-crystal diffraction (II), and laser-radiation second harmonic generation. Structure I is solved using the Patterson function and refined by the Rietveld method. Both compounds crystallize in the monoclinic crystal system. For crystals I, the unit cell parameters are as follows: a = 15.6411(1) Å, b = 11.1909(1) Å, c = 9.6981(1) Å, β = 90.119(1)°, space group C2/c, R _p = 4.02%, and R _wp = 5.25%. For crystals II, the unit cell parameters are as follows: a = 9.965(2) Å, b = 11.612(2) Å, c = 15.902(3) Å, β = 90.30(3)°, space group P2₁/n, R ₁ = 4.43%, and wR ₂ = 10.76%. Structures I and II exhibit a similar topology of the networks which are built up of { In[PO₄]₂} (I) and { In₂[PO₄]₄} (II) structural units.     

Synthesis of Boron-Containing Siloxanes by Reaction of Hydroxy-<Emphasis Type="Italic">closo</Emphasis>-Decaborates with Dihalosilanes

A new approach to the preparation of boron-containing siloxanes based on cluster boron anions has been suggested. This approach consists in the reaction of hydroxy derivatives of closo-decaborate anion [B₁₀H_10–n(OH)_n]^2– (n = 1, 2) with dihalosilanes SiR₂Cl₂ (R = CH₃, _t- C₄H₉, C₆H₅). The obtained compounds have been characterized by IR, ESI/MS, and NMR (1H, 11B, 13C) spectroscopy.     

Simulation and interpretation of the vibrational spectra of heterofullerenes

This paper reports on a computer simulation of the vibrational spectra of C₅₉B, C₅₉N, C₅₉BN, and C₅₉HN. The modes whose frequencies are most sensitive to carbon substitution by heteroatoms are revealed. It is shown that the new bands at 818, 839, and 845 cm⁻¹ in the experimental IR spectrum of C₅₉HN arise from changes in selection rules and by removal of degeneracies due to a reduction in the symmetry of the molecule and force field perturbation. In the Raman spectrum of C₅₉HN, the shifts of the 1460 and 491 cm⁻¹ bands to the low-frequency region by 7 and 3 cm⁻¹, respectively, relative to two A_g modes of C₆₀ are explained by the perturbation induced by the N and C(H) atoms in the force field of adjacent CC bonds not containing these atoms. Institute of Spectroscopy, Russian Academy of Sciences (Troitsk, Moscow Region). Scientific and Production Association “Complex.” Scientific and Production Association “Tekhon.” Translated fromZhurnal Strukturnoi Khimii, Vol. 39, No. 3, pp. 401–411, May–June, 1998.     

Synthesis of Hafnium(IV) Polyaminoacetates

The interaction of hafnium(IV) salts (oxide-dichloride, chloride, and bromide) with nitrilotriacetic acid (NTA), diethylenetriamminepentaacetic acid (DTPA), 1,2-diaminocyclohexanetetraacetic acid (CDTA), 1,3-dipropylmino-2-hydroxy N,N,N′,N′-tetraacetic acid (dpta), and N-(2-hydroxyethyl)ethylenediamine triacetic acid (HEDTA) has been studied. The corresponding complexes Na₂[Hf(NTA)₂]·3H₂O (1), Na[HfDTPA]·3H₂O (2), [HfCDTA(H₂O)₂] (3), and Na[Hf₂(dpta)₂]·7.5H₂O·0.5C₂H₅OH (4) have been isolated and characterized and their structures have been determined by single crystal X-ray diffraction. Biological studies of [HfCDTA(H₂O)₂] have shown that in 5% glucose solution this complex has low toxicity and good contrasting ability.