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Mutnovskite, ideally [Pb.sub.2]As[S.sub.3](I,Cl,Br), is a new mineral from the high-temperature fumaroles of the Mutnovsky volcano, Kamchatka Peninsula, Russian Federation. It occurs as microscopic ruby-colored short-prismatic crystals up to 100 [micro]m across, closely associated with halogen-sulfosalts of Pb, Bi, and As, Cd-Pb-Bi sulfosalts, pyrite, anhydrite, and cristobalite. Mutnovskite is transparent in thin fragments with a dark-red to blue color. The crystals are soft and fragile. Cleavage and fracture were not observed and the Mohs hardness is approximately 2. In reflected light mutnovskite is silvery lead-grey in color with an iridescent tarnish. Pleochroism and anisotropy are not visible because of the strong orange internal reflections, especially in immersion. Reflectance percentages measured in air in the range 400-700 nm were tabulated. Reflectance percentages ([RM.sub.min], and [R.sub.max]) for the four COM wavelengths are 34.2, 34.6 (470 nm), 33.2, 33.5 (546 nm), 32.5, 32.7 (589 nm), and 31.4, 31.7 (650 nm), respectively. A mean of four electron microprobe analyses gave Pb 62.0(3), As 11.0(4), Bi 0.6(1), S 14.4(2), Se 0.2(3), I 8.9(3), CI 2.44(9), Br 1.1(7), Cu 0.03(2), Fe 0.01(1), total 100.7 wt%, corresponding, on the basis of a total of 7 atoms, to [Pb.sub.1.99][([As.sub.0.98][Bi.sub.0.02])).sub.[summation]1.00] [([S.sub.2.98][Se.sub.0.02]).sub.[summation]3.00][([I.sub.0.47][Cl.sub.0.46] [Br.sub.0.09]).sub.[summation1.02]. The nine strongest powder-diffraction lines [d in [Armstrong] (I/[I.sub.0])(hkl)] are: 4.69 (32) (002): 4.37 (67) (210): 3.34 (73) (020); 3.19 (100) (212); 2.715 (61) (022); 2.648 (66) (410); 2.539 (31) (213); 2.455 (29) (402); 1.894 (30) (232). Mutnovskite is orthorhombic, space group Pnma, with a = 11.543(1), b = 6.6764(7), and c = 9.359(1) [Armstrong], V = 721.3(1) [Armstrong], Z = 4. The crystal structure was solved and refined to R = 4.14%. It consists of three independent cation positions: Pb 1 and Pb2 have tricapped trigonal prismatic coordinations with S and I atoms (completed with one As atom in the case of Pb2), while As has threefold coordination with S atoms, which form the base of a trigonal pyramid with As at the apex. Pairs of Pb1-Pb2 prisms are connected in columns which extend along c. As[S.sub.3] coordinations are isolated from each other. S atoms and half of the Pb atoms form wavy close-packed layers. Two kinds of channels parallel to b occur between the layers. The smaller channels host As atoms close to the channel walls, with their lone-electron pairs occupying the median part, while the bigger ones accommodate rows of alternating halogen and Pb atoms. The new mineral is named after the type locality, the Mutnovsky volcano, Kamchatka Peninsula, Russian Federation. Keywords: Mutnovskite, chemical composition, new mineral, X-ray data, crystal struture, Kamchatka Peninsula, Mutnovsky volcano

Parallel batch screening experiments were carried out to examine how displacer chemistry and salt counterions affect the selectivity of batch protein displacements in anion exchange chromatographic systems. The results indicate that both salt type and displacer chemistry can have a significant impact on the amount of protein displaced. Importantly, the results indicate that, by changing the displacer, salt counterion, or both, one can induce significant selectivity changes in the relative displacement of two model proteins. This indicates that highly selective separations can be developed in ion exchange systems by the appropriate selection of displacer chemistry and salt counterion. The experimental batch screening data were also used in conjunction with various molecular descriptors to generate quantitative structure efficacy relationship (QSER) models based on a support vector machine feature selection and regression tool. The models resulted in good correlations and successful predictions for an external test set of displacers. A star plot approach was shown to be a powerful tool to aid in the interpretation of the QSER models. These results indicate that this modeling approach can be employed for the a priori prediction of displacer efficacy as well as for providing insight into displacer design and the selection of proper mobile-phase conditions for highly selective separations.

Research has been conducted on pareitropone. The synthesis of this compound carried out via the application of alkynyliodonium salt chemistry is described.

Research has been conducted on the optically active 4-methylcyclohexylidenemethyliodonium tetrafluoroborate. The preparation and solvolysis of this compound have been carried out in different solvents and the results indicate that the primary vinyl cation is not involved in the reactions.

Phosphorus chemical shift and [sup.31]P,[sup.31.]P spin-spin coupling tensors have been characterized for pentaphenylphosphinophosphonium tetrachlorogallate, [[Ph.sub.3]P-P[Ph.sub.2]][Ga[Cl.sub.4]], using solid-state [sup.31.]P NMR spectroscopy. Spectra obtained with magic-angle spinning yield the isotropic value of the indirect spin-spin coupling, |[sub.1]J[(sup.31]P,[sup.31]P)[sub.iso]|, 323 [+ or -] 2 Hz, while 2D spin-echo and rotational resonance experiments provide the effective dipolar coupling constant, [R.sub.eff], 1.70 [+ or -] 0.02 kHz, and demonstrate that [J.sub.iso] is negative. Within experimental error, the effective dipolar coupling constant and [J.sub.iso] are unchanged at -120[degrees]C. The anisotropy in [sup.1]J([sup.31]P,[sup.31P]), [DELTA] J, has been estimated by comparison of [R.sub.eff] and the value of the dipolar coupling constant, [R.sub.DD], calculated from the P--P bond length as determined by X-ray diffraction. It is concluded that |[DELTA]J| is small, with an upper limit of 300 Hz. Calculations of [sup.1]J([sup.31]P[sup.31]P) for model systems [H.sub.3]P-P[H.sup.+.sub.2] and [(C[H.sub.3).sub.3]]P-P[([CH.sub.3).sup.+.sub.2]] using density functional theory as well as multiconfigurational self-consistent field theory ([H.sub.3]P-P[H.sup+.sub.2]) support this conclusion. The experimental spin-spin coupling parameters were used to analyze the [sup.31]p NMR spectrum of a stationary powder sample and provide information about the phosphorus chemical shift tensors. The principal components of the phosphorus chemical shift tensor for the phosphorus nucleus bonded to three phenyl groups are [[delta].sub.11] = 36 ppm, [[delta].sub.22] = 23 ppm, and [[delta].sub.33] = -14 ppm with an experimental error of [+ or -]2 ppm for each component. The components are oriented such that [[delta].sub.33] is approximately perpendicular to the P--P bond while [[delta].sub.11] forms an angle of 31[degrees] with the P--P bond. For the phosphorus nucleus bonded to two phenyl groups, the principal components of the phosphorus chemical shift tensor are [[delta].sub.11] = 23 ppm, [[delta].sub.22] = -8 ppm, and [[delta].sub.33] = -68 ppm with experimental errors of [+ or -]2 ppm. In this case, [[delta].sub.33] is also approximately perpendicular to the P--P bond; however, [[delta].sub.22] is close to the P--P bond for this phosphorus nucleus, forming an angle of 13[degrees]. The dihedral angle between the [[delta].sub.33] components of the two phosphorus chemical shift tensors is 25[degrees]. Results from ab initio calculations are in good agreement with experiment and suggest orientations of the phosphorus chemical shift tensors in the molecular frame of reference. Key words: Nuclear magnetic resonance spectroscopy, phosphorus chemical shift tensors, [sup.31]P-[sup.31]P J-coupling tensors, density functional theory, multiconfigurational self-consistent field theory, phosphinophosphonium salts.

Three different [KNO.sub.3] salts with [[delta].sup.18]O values ranging from about -31 to +54 [per thousand] relative to VSMOW were used to compare three off-line, sealed glass tube combustion methods (widely used for isotope studies) with a more recently developed on-line carbon combustion technique. All methods yielded roughly similar isotope ratios for [KNO.sub.3] samples with [[delta].sup.18]O values in the midpoint of the [[delta].sup.18]O scale near that of the nitrate reference material IAEA-NO-3 (around +21 to +25[per thousand]). This reference material has been used previously for one-point interlaboratory and intertechnique calibrations. However, the isotope ratio scale factors by all of the off-line combustion techniques are compressed such that they are between 0.3 and 0.7 times that of the on-line combustion technique. The contraction of the [[delta].sup.18]O scale in the off-line preparations apparently is caused by O isotope exchange between the sample and the glass combustion tubes. These results reinforce the need for nitrate reference materials with [[delta].sup.18]O values far from that of atmospheric [O.sub.2], to improve interlaboratory comparability.

A novel transduction chemistry for preparing optical anion-selective polymeric films that respond reversibly and selectively to chloride ion activity is demonstrated. The chloride sensors are prepared by casting thin (5-10 [micro]m) plasticized PVC films containing indium(III) octaethylporphyrin hydroxide, along with optimized levels of a lipophilic tetraphenylborate salt, onto glass slides. When bathed in low-pH buffered solutions void of chloride, the porphyrin species spontaneously forms a hydroxide ion-bridged dimer, with the added lipophilic borate species serving as the counteranion for this complex. The maximum for the Soret absorption band of this dimeric species is shifted to 390 nm, from 410 nm for the initial monomeric porphyrin. Increases in chloride ion levels in the bathing solution results in chloride extraction and ligation to the [In.sup.III] center, and concomitant breaking of the dimer into monomeric porphyrin species, yielding a decrease in absorbance at 390 nm and an increase in optical signal at 410 nm. Under optimized conditions, optical selectivity coefficients toward chloride over a wide range of other anions (N[O.sub.3.sup.-], Cl[O.sub.4.sup.-], SC[N.sup.-], S[O.sub.4.sup.2-], [F.sup.-], [Br.sup.-], [H.sub.2]P[O.sub.4.sup.-]) are measured to be < [10.sup.-3]. Of all anions tested, only salicylate yields a slightly greater response than chloride. This selectivity is shown to be adequate for reversible and accurate sensing of chloride levels in diluted serum samples.

Apparent molar volumes ([V.sub.2,[PHI]]) and standard partial-molar volumes ([V.sup.0.sub.2,[PHI]]) of LiCl[O.sub.4] and LiBr at 298.15 K have been determined from precise density measurements in solvent mixtures of propylene carbonate (PC) with dimethylformamide (DMF), tetrahydrofuran (THF), acetonitrile (AN), and methyl formate (MF). The scaled particle theory is used to calculate the contributions of the cavity formation and the electrolyte-solvent interactions to the standard partial-molar volumes. It is shown that [V.sup.0.sub.2,[PHI]] is strongly dependent on the nature of the solvents, and the trends in [V.sup.0.sub.2,[PHI]] with composition of the solvent mixtures are determined by the interaction volumes of electrolytes with solvents. The results are discussed in terms of ionic preferential solvation, packing effect of solvents in the solvation shell, and electrostriction of solvents by ion. Key words: partial-molar volume, scaled particle theory, lithium salts, propylene carbonate, solvent mixtures, lithium battery electrolytes.

Research has been conducted on the copper(I)-acetonitrile complexes. The synthesis of the two-coordinate copper(I) compound ligated by nitrile ligands has been carried out and the results indicate that use of this compound for copper(I) complex synthesis can lead to solubility in low-dielectric solvents.

Flavylium salts substituted at the 4-position have been prepared according to a Grignard reaction of some flavones with appropriate alkyl- and aryl-magnesium bromides. Among these compounds, 4-methyl flavylium salts were gently reacted with aromatic aldehydes, affording new anthocyanidin pigments, some of which are of the vitisin family. These are the first examples of chemically synthesized vitisidins (aglycones of vitisins). Compared to the more common flavylium salts, they demonstrate a large bathochromic shift (from about 100-200 nm), thus providing blue-violet and green colours, so difficult to obtain with anthocyanidins in general. Key words: 4-substituted flavylium chlorides, vitisin aglycones, blue-violet and green anthocyanidin pigments.

The infrared spectra of ten salts in aqueous solutions were obtained in their solubility range using attenuated total reflection (ATR). The salts are: LiCl, NaCl, KCl, CsCl, Mg[Cl.sub.2], NaBr, KBr, NaI, KI, and CsI. The salts, which are completely ionized in water, do not absorb in the IR. Only their interactions with water are observed and analyzed. Factor analysis (FA) applied to the spectra showed that two principal species are present in the solutions: pure water and salt-solvated water. The modifications of the water spectrum are dependent on the nature of the salts, their concentrations and are mainly of first-order. Second-order effects were observed but, being weak, were not investigated. The modifications of the IR-ATR spectrum from pure water to a salt solution are proportional to the modifications of the imaginary part of the refractive index spectrum (k(v)). This indicates that the anomalous dispersion effects do not interfere with the chemical analysis of the IR-ATR spectra. In every salt studied, the two main species present in the solutions remained stable throughout the salt solubility ranges. Comparison between the IR spectra of the different salts solutions indicates that both anions and cations are in strong interaction with water molecules and are solvated together in stable clusters. Key words: IR spectroscopy, ATR, liquid, aqueous solutions, factor analysis, principal spectra, LiCl, NaCl, KCl, CsCl, NaBr, KBr, NaI, KI, CsI, Mg[Cl.sub.2].

The principal components of the carbon, nitrogen, and selenium chemical shift (CS) tensors for several solid selenocyanate salts have been determined by NMR measurements on stationary or slow magic-angle-spinning powder samples. Within experimental error, all three CS tensors are axially symmetric, consistent with the expected linear geometry of these anions. The spans [OMEGA] of the carbon and selenium CS tensors for the selenocyanate anion (SeC[N.sup.-]) are approximately 300 and 800 ppm, respectively, much less than the corresponding values for carbon diselenide (CSe2). This difference is a consequence of the difference in the CS tensor components perpendicular to the C[varies] symmetry axes in these systems. Ab initio calculations show that the orbital symmetries of these compounds are a significant factor in the shielding. For CS[e.sub.2], efficient mixing of the [sigma] and [pi] orbitals results in a large paramagnetic contribution to the total shielding of the chemical shielding tensor components perpendicular to the molecular axis. Such mixing is less efficient for the SeC[N.sup.-], resulting in a smaller paramagnetic contribution and hence in greater shielding in directions perpendicular to the molecular axis. Key words: selenocyanates, solid-state NMR, carbon shielding tensors, nitrogen shielding tensors, selenium shielding tensors, ab initio calculations.

Three 2-deoxy-[alpha]-[ETH]-glucopyranosyl pyridinium tetrafluoroborates were tested for their binding affinity to a range of [alpha]-glucosidases and [alpha]-mannosidases. The [alpha]-isoquinolinium salt (11) binds approximately 275-fold more tightly to yeast [alpha]-glucosidase than does the isomeric quinolinium salt (12). In addition, compound 11 binds to the yeast enzyme approximately two-fold tighter than the corresponding glucopyranosyl isoquinolinium salt (9). The ([k.sub.cat]/[k.sub.hyd]) values for the yeast [alpha]-glucosidase-catalyzed reactions of 11 and 9 are 1.6 x [10.sup.5] and 2.0 x [10.sup.9], respectively, when compared to the spontaneous uncatalyzed reactions. Thus, the interaction of the 2-OH group in compound 9 with the yeast enzyme's active site generates a relative transition state stabilization of about 23.5 kJ [mol.sup.-1]. For both compounds 11 and 12, the observed rate accelerations for the yeast [alpha]-glucosidase-catalyzed hydrolysis, relative to the spontaneous reaction in solution, ([k.sub.cat]/[k.sub.hyd]) are identical within experimental error. Key words: glycosidase, inhibitor, 2-deoxyglucose, pyridinium, catalysis.

Two dimensional deuterium NMR measurements are reported for three different onium salts [(C[H.sub.3]).sub.3]SeN[O.sub.3]-[d.sub.3], [(C[H.sub.3]).sub.3]TeI-[d.sub.3], and [(C[H.sub.3).sub.3]SI-[d.sub.9]. In these molecular solids with the general structure [(C[H.sub.3]).sub.3][E.sup.+][X.sup.-], three methyl groups are attached to the E atom. There is the possibility of reorientation of the methyls about their [C.sub.3] axes and reorientation of the whole tri-methyl group about the [C'.sub.3] axis. From an analysis of the 2D NMR exchange spectra the angle between the E--C bonds and the rotation axis for trimethyl reorientation were determined. Exchange rates and spin lattice relaxation times are given for several temperatures, to show how the mixing times for the experiments were selected. The data presented for [(C[H.sub.3]).sub.3]TeI-[d.sub.3], demonstrate that 2D techniques are sensitive to motions on a time scale an order of magnitude slower than that accessible using 1D line shape techniques. Key words: deuterium NMR, molecular motion, onium salts, two dimensional spectra.

Pseudo-steady-state and time-resolved chemically-induced dynamic nuclear polarization (CIDNP) experiments were done to study the photodecomposition of triphenylsulfonium hexafluoroantimonate. 9,10-dimethylanthracene and naphthalene were used as the singlet sensitizers. Results indicated that the deactivation pathways of the radicals differ considerably based on CIDNP spectra. This finding arises from the observation that the intermediate phenyl radical can abstract hydrogen from the radical cation of 9,10-dimethylanthracene but not that of naphthalene.

Research has been conducted on carboxy-substituted alkylammonium salt. The preparation of this salt and its use as incoming carboxylate ligand in a ligand-exchange reaction to produce Mn (sub)12 single-molecule magnet are described.

Research has been conducted on silver(I) double salts containing 4-hydroxyquinoline ligand. The authors describe the synthesis of these salts carried out via the hydrothermal method.

Research has been conducted on metal-centered ferrocene compounds. The authors report that these compounds have been designed via the use of 5-ferrocenylpyrimidine and ferrocenylpyrazine, and that when combined with transition metal salts they produce structurally diverse mixed-metal polynuclear complexes.

Research has been conducted on zeolite continuous coating formation. The authors have reversed the surface charge of the exposed catalyst's surface via the use of copolymer of acrylamide and methyl chloride quaternary salt.

Research has been conducted on noncyclic [10-S-5] sulfuranide dioxide salts with three S-C bonds. The authors describe the synthesis of these compounds which started from various sulfur electrophiles, and their characterization.

Research has been conducted on quaternary salts of pyridine, pyridazine, N-methyl imidazole and N-propyl triazole containing pentafluorosulfanyl. The authors describe the preparation and characterization of these salts carried our via the use of (super)13 C NMR and IR spectra and elemental analyses.

Research has been conducted on pyridine-2-dicarboxylic-, pyridine-2,6-dicarboxylic- and pyridine-2,4-dicarboxylic acids and their salts. The authors demonstrate that these compounds react with triply bonded dirhenium(II) complex is respond to ethanol, and produce unsymmetrical substitution products where N,O represents a chelating pyridine-2-carboxylate ligand.

Research has been conducted on [Ge (sub)9 =Ge (sub)9 =Ge (sub)9 =Ge (sub)9] (super)8-, a tetramer possessing nine-atom deltahedral germanium clusters and charge 8-. The authors describe the characterization of this compound as salt.

Research has been conducted on oxadiazole-containing rigid bidentate ligands with inorganic Ag(I) salts. The authors have invetsigated the coordination chemistry of these ligands, and present the results.

Research has been conducted on angular trinuclear copper(II) complexes containing Schiff base obtained from salicylaldehyde condensation. The authors describe the preparation of these complexes in the presence of imidazole, and their isolation as perchlorate salts.

Research has been conducted on copper(III) complexes of bis(tacn) ligands. The authors describe the preparation of these complexes via the reaction of Cu(II) salt with L.6HCl in neutral aqueous solution.

Research has been conducted on uranyl and strontium nitrates, and uranyl chlorides. The authors have compared the solvation of these compounds in room-temperature ionic liquids, and have presented the results.

Research has been conducted on alkene aziridination. The authors describe the location of transition structures for this aziridination via the use of substituted oxaziridines and diaziridinum salts.

The authors review the publications on box ligands with pyridine ring as a spacer. The topics include the synthesis of these ligands, the preparation of the catalysts via the reaction of pybox with inorganic salts, and the characterization of pybox ligands via the single-crystal X-ray structural study.

Research has been conducted on mu-phenoxo-bis-mu-acetato di-manganese(II) complex using BpmpH ligand. The authors describe the isolation of this complex as a perchlorate salt, and report that X-ray structure of the complex has two manganese(II) ions which are in a distorted octahedral environment.

Research has been conducted on 2D bilayer cobalt(II)-organic framework with nanoscale rectangular channels clathrating large organic molecules. The authors describe the synthesis of this framework carried out via the reaction of cobalt(II) salt with 5-nitro-1,3-benzenedicarboxylic acid and 1,2-bis(4-pyridyl)ethylene.

Research has been conducted on tetracycline derivatives. The authors report the synthesis of these derivatives which utilizes Suzuki, Heck and other palladium-coupling reactions by means of tetracycline iodoarene and arenediazonium salts.

Research has been conducted on tridentate Schiff base carboxylate ligands. Results demonstrate that these ligands react both with copper trifluorate salt to produce helical chain complex and with copper nitrate to give tetranuclear complex with azide salt.

Research has been conduucted on copper(I)-acetonitrile solutions. The authors report that the study of Cu (super)63 NMR line width in these solutions has been carried out, and that different variants of Cu(I) salt concentrations, added salts, chloride ion, water and temperature have been investigated.

Research has been conducted on silylketene dithioacetal. The authors demonstrate that the acid-catalyzed reactions of this compound with imines or iminium salts produce gamma,gamma-bis(ethylthio)allylamines.

Research has been conducted on terephthalic acid, salicylidene alkylimine, NaOH and inorganic manganese(II) or (III) salt. Results demonstrate that the reaction system consisting of these compounds produses dinuclear manganese complexes.

Research has been conducted on diimine-type ligands. The authors describe the reactions of protic nucleophiles with these ligands carried out in the presence of iron(II) salts.

Research has been conducted on tripodal ligands. The reaction of these ligands with metal salts has been carried out, and the results demonstrate that this reaction has produced two-dimensional metal-organic frameworks.

Research has been conducted on soluble hexa-peri-hexabenzocoronene. The synthesis of this compound carried out from hexaphenylbenzene is described.

Research has been conducted on K (sub)5 Bi (sub)4 metallic salt. The authors have investigated the electronic structure of this salt via the use of first-principles density functional calculations, and they report that alkali and pnictide orbitals contribute to the stability of the compound.

Research has been conducted on ionic salts of ruhtenium(IV). The authors describe the synthesis of these salts, and demontrate that their structures have been determined via single-crystal X-ray diffraction.

Research has been conducted on bicyclic sulfonium salts. The authors discuss the enantioselective synthesis of these compounds or swainsonine derivatives' thioanalogues which is based on a stereo- and regiospecific transannular cyclization reaction of cyclic sulfides.

Research has been conducted on vinamidinium salts. The authors report the use of the derived from dimedone enaminones as starting materials, and the presence of rotameric vinamidinium salts as well as diastereomeric vinylogous imidate salts characterized via (super)1 H NMR.

The author discusses publications on polyvalent iodine compounds, such as pentacoordinate I(V) and tricoordinate I(III). The topics of interest include the role of these compounds in contemporary organic chemistry, and the chemistry and uses of aryl-, alkenyl- and alkyliodonium salts in synthetic and preparative organic chemistry.

Research has been conducted on [Cu (super)II (hfac) (sub)2 (TTF-py) (sub)2](PF (sub)6).2CH (sub)2 Cl (sub)2 where hfac=4-(2-tetrathiafulvalenyl-ethenyl. The authors describe the preparation, EPR data, X-ray crystal structure and magnetic measurements of this compound in which localized spin and conducting systems are covalently linked via conjugated bridges.

Research has been conducted on beta-amino alcohols produced by cyclohexene oxide and containing alpha-phenylethyl auxiliaries. The authors report that these compounds act as chiral promoters during the addition of diethylzinc to benzaldehydes.

Research has been conducted on [3+3] cycloaddition reaction . The description of this reaction carried out via the use of 4-hydroxy-2-pyrones and 1,3-diketones is presented.

Research has been conducted on ethyl N-[(2-Boc-amino)ethyl]glycinate and its hydrochloride salt. The improved synthesis of these compounds is described.

Research has been conducted on century-old copper salt. The authors report their study of the structure, magnetism and spectroscopy of this salt.