SO4 Groups Research Articles

Phononspectroscopy and lattice dynamical calculations of anhydrite and gypsum

Detailed experimental and theoretical studies of the k=0 vibrational spectra of anhydrite and gypsum are reported. The dielectric constants and the infrared reflection and Raman spectra of the single crystal have been measured. The frequencies of the phonon spectrum, the contribution of potential terms to potential energy and detailed mode assignments have been determined based on a polarizable-ion model. The relative experimental intensity of the spectra, the observed crystal field effects, the rotatory lattice modes of the H2O molecule and the mixed character of translatory and rotatory modes of the Ca, SO4, and H2O groups are discussed based on the theoretical vibrational modes and the potential energy distribution. The principal moments of inertia of the water molecule and the Lennard-Jones potential constants for nonbonded oxygen-oxygen interactions are presented.

Infrared band intensities of saturated hydrocarbons

Kramers-Kronig analysis is applied to measured values of spectral reflectance at near-normal incidence to determine the real and the imaginary parts of the complex index of refraction for methane, ethane, propane, n-butane, n-hexane, n-heptane, and n-decane in the liquid state. The results indicate that the strengths of the characteristic bands as measured by the integral of the imaginary part are roughly constant for all the liquid alkanes except for methane. The intensity of the CH valence vibration bands in the spectra of the alkanes except methane is directly proportional to the number of CH groups per unit volume. The relations for the intensity of the bands due to CH2 and CH3 deformations are examined. Characteristic band intensities of the type established for NH4(+) and SO4(2-) groups in solutions and crystals cannot be extended to the more closely coupled CH2 and CH3 groups in alkane molecules.

Spectres Raman d'un Monocristal de As2O3, SO3 et Calcul du Champ de Force

AbstractThe polarized Raman spectra of a single crystal of As2O3, SO3, along with the infrared spectra of this compound in the polycrystalline state have been investigated at 30 K and 300 K in the 20–4000 cm−1 range. The dependance of the frequency shift of polar vibrations with the geometry of the Raman experiments has also been studied. An assignment in terms of symmetry species is proposed for 49 of the 51 expected active modes. A normal coordinate calculation using a valence force field has been performed for the principal vibrations (k ⋍ 0) of the crystal. The good agreement between observed and calculated frequencies shows that long range forces are negligible compared to internal valence forces. There are two different SO bonds characterized by stretching force constants of 9.1 and 5.2 mdyn Å−1 and SO bond lengths have been estimated equal to 1.44 and 1.56 Å respectively, by using an empirical correlation. The AsO stretching force constants of the OAsOAs…︁ chains and of the bonds linking As and SO4 groups are similar: 2.0 and 1.9 mdyn Å−1 respectively. Therefore the crystal is not an ionic sulphate compound.

STUDIES ON MONOAMINE OXIDASE (REPORT XXXIV).: EFFECTS OF AMMONIUM SULFATE ON MITOCHONDRIAL MAO IN BEEF LIVER

The effects of ammonium sulfate on mitochondrial monoamine oxidase (MAO) in beef liver were studied. The initial stage of the reaction was measured with an oxygen electrode and the long term reaction was measured manometrically. With tyramine or benzylamine as substrate, addition of ammonium sulfate increased the initial reaction but decreased the long term reaction. Ammonium sulfate had similar effects on solubilized MAO. Inhibition of MAO activity in both the initial and long term reaction by excess substrate was diminished by addition of ammonium sulfate. The effects of ammonium sulfate on MAO were reversible. Salts having an -SO4 group, such as Na2SO4 and K2SO4, increased MAO activity in the initial reaction while salts having an -NH4 group, such as NH4Cl and NH4NO3, inhibited it. However, all these salts inhibited MAO activity in the long term reaction. The mechanism of activation of MAO activity by addition of ammonium sulfate is discussed.

Crystal structure of tritin(II) dihydroxide oxide sulphate

The crystal structure of the title compound has been determined from X-ray diffractometer data by Patterson and Fourier methods. Crystals are orthorhombic and piezoelectric, space group Pbc21 with Z= 4 in a unit cell of dimensions a= 4.983 ± 0.002, b= 13.1 28 ± 0.005, c= 1 2.214 ± 0.005 A. The structure was refined by least-squares methods to R 0.028 for 1 070 reflections. The structure contains discrete ring [Sn3O(OH)2]2+ basic ions which have Sn in two different environments : one Sn is bonded to all three ring oxygens to give trigonal pyramidal co-ordination with short Sn–O, and the remaining Sn atoms are bonded to two ring O atoms with short Sn-O ( 2.40 A) distances. These latter Sn atoms have distorted square-pyramidal oxygen environments. The bonds between the SO4 groups and the basic ion Sn atoms result in the formation of a layer structure.

Raman Spectra of Hexagonal Ethylsulfates of Yttrium and of some Rare Earths

The phonon Raman spectra of single crystals of Y(C2H5SO4)3•9H2O, Ce(C2H5SO4)3•9H2O, Nd(C2H5SO4)3•9H2O, Sm(C2H5SO4)3•9H2O have been studied at low temperatures with laser excitation. Some information has also been obtained of the compounds of Ho3+ and Er3+. The types of symmetry of the observed modes have been determined and compared with the results of a group theoretical calculation. The internal modes of the C2H5 and SO4 groups and of the H2O molecules can be completely attributed to observed transitions. There is some evidence to attribute the librational modes of the H2O molecules to transitions which show a very pronounced temperature dependence of the line-widths. Reasons for this temperature dependence are discussed. No lines have been found that can be attributed uniquely to electronic transitions.

Laser Raman Spectrum of Triglycine Sulfate

Abstract The laser Raman spectrum of ferroelectric triglycine sulfate has been determined by the use of an argon ion gas laser. The observed Raman lines are compared with reported assignments in the literature by Taurel1 and Krishnan2, Determination of depolarization ratio of the sulfate line at 980 cm−1 shows that the Raman band is highly polarizable and the molecular vibration is totally symmetrical v1. The role played by the glycine groups in the spontaneous polarization and its reversal can be indirectly confirmed by Raman spectrum of TGS. Interpretation of the Raman spectrum indicates that the SO4 groups do not have tetrahedral symmetry at roan temperature. Ferroelectric behavior of TGS is attributed to the glycine groups.

Selenourea complexes of palladium

1. New compounds with selenourea were produced: [PdSeU4]SO4; [PdSeU3SO4]; [PdSeU2SO4H2O]; [PdSeU4](SCN)2; [PdSeU2(SCN)2], in which selenourea (SeU) is bonded to the metal through the selenium atom. 2. In the compounds PdSO4·3SeU; PdSO4·2SeU·H2O the SO4 group is in the inert sphere.

Raman Spectrum of Gypsum

The Raman spectrum of an oriented single crystal of CaSO4∙2H2O has been recorded from 20 to 3600 cm−1 at 300 °K and 77 °K using polarized laser excitation. The symmetries of the observed Raman lines have been determined and the spectrum has been analyzed in terms of external lattice vibrations, internal vibrations of the SO4 and H2O groups, hydrogen bond vibrations, and combinations of these vibrations. The translatory and rotatory lattice modes of the H2O molecules have been identified and the latter have been correlated with the principal moments of inertia of the water molecule. The hydrogen bond vibration was observed at 210 cm−1 at 300 °K and 217 cm−1 at 77 °K. The assignments of the internal modes were found to be consistent with the results of previous workers. Several overtone and combination frequencies were observed, especially in the region of the ν1 and ν3 vibrations of H2O.

Interionic forces in crystals—II. Infrared spectra of SO4 groups and “octahedrally” coordinated water in some alums, Tutton salts, and the double salts obtained by dehydrating them

Abstract Infrared spectra of 22 alums (including α, β and γ types) show simple v 3 and v 4 sulfate vibrational peaks indicating essentially T d symmetry, plus numerous peaks due to water coordinated about the M''' and M' ions. There are few simple correlations of spectra with change in either cation, but the position of v 3 is slightly affected by change from α to β structure. Infrared spectra of 18 Tutton salts are more sensitive to the nature of the M' cation than to the M'' cation. The effective SO 4 symmetry is C 3 v . Infrared spectra of 24 dehydrated alums fall into two main symmetry patterns for SO 4 , C 3 v , for Al''' and C 2 v , (probably) for other M''' ions. The spectral lines are remarkably sharp and intense, and depend more on the nature of the M''' than on the M' cations. The rock and wag frequencies for waters “octahedrally” coordinated to M''', M'', and M' cations can be systemized in terms of ionic charge and presence or absence of d orbitals in the cation.

Thermal motion of the sulfate group in sodium alum NaAl(SO4)2.12H2O

In the structure refinement of Na alum]by,Cromer, Kay & Larson'([Acta Cryst. (1967). 22, 182])the unusual anisotropic thermal parameters of the SO4 group were explained by a coupled rotation about and translation along the threefold axis. S and O(1) are on the threefold axis and 0(2) is in a general position. 0(2) thus follows a spiral path on the surface of a cylinder. In the present work the scattering over the spiral path was calculated by integrating numerically and taking numerical derivatives. It was then evident that a torsional oscillation also exists. Based on the formation developed by Kay & Behrendt, a model that adds a torsional oscillation to the screw motion was calculated. In addition, thermal parameters parallel and perpendicular to the threefold axis were applied to the whole group. The thermal motion is then described by only five parameters instead of the ten used in the earlier anisotropic refinement. A result of this treatment is that the bond lengths can be expressed in terms of equilibrium positions and are as accurate as the data and potentials allow. The resulting bond lengths are S-O(1)= 1.476 (6) and S-O(2)= 1.491 (4) .~. The uncorrected lengths from the anisotropic refinement are 1.461 and 1.459 .~. The Cruickshank rigid body correction increases these bond lengths to 1.475 and 1-483/~ and the Schomaker-Trueblood analysis increases them to 1.476 and 1.500/~,.

Structure Transition in Alkali Silicate Glasses

The logarithm of measured high‐temperature fluidities is related to the square of the calculated probability of finding a nonbridging oxygen in a randomly chosen SO4 group. This is interpreted in terms of a flow mechanism (gliding) dependent on juxtaposition of two such oxygens. A theory of the glass transformation is developed. On cooling, the coordination number of nonbridging oxygens increases until, ideally, at T, each touches three oxygens of an external Si04 group (stabilization). Below this temperature, thermal expansion/contraction contains no coordination change component. These changes constitute a second‐order transition. Observed volume data are in agreement with hypothesis. On this view, stabilization creates vacant tetrahedral environments adjacent to existing ones. Migration of glass‐forming ions to these empty sites can unlock the structure and permit the operation of a new set of flow processes. The coordination requirements for stabilization severely restrict the types of local arrangement possible at high silica contents, and therefore reduce the configurational entropy and induce unmixing. The overall transformation is composite in character. Rather extensive bond rearrangement and unmixing (when present) are features of first‐order kind.

Comparative study of the localization of incorporated 14C-labeled amino acids and 35SO 4 in the sea urchin ovary, egg and embryo

1. 1. The incorporation of 14C-labeled amino acids and of 35SO 4 into the ovary, oocyte, egg and embryo of the sea urchin was studied by means of autoradiography combined with histochemical analysis. The species employed were Echinus esculentus, Paracentrotus lividus, Psammechinus miliaris and Sphaerechinus granularis. 2. 2. Precursors were injected into the body cavity of the adult female, and labeling was observed in sections of the ovary as well as in sections of eggs and embryos obtained from eggs removed from the ovary. The extent of incorporation depended on the degree of maturity of the eggs at incubation, and on the species. 3. 3. The first site of incorporation of 14C is the nucleolus of the oocyte. It is inferred that amino acids are complexed with low-polymer RNA, which accumulates in the outer rim of the nucleolus. From this site the low-polymer RNA-amino acids complex migrates into the germinal vesicle and thence, into the cytoplasm. 4. 4. Labeled sulfate is incorporated directly into the cytoplasm of the oocyte. The distribution is random at first, but as the maturation proceeds, the labeled area becomes limited to the cortex. 5. 5. Eggs labeled while in the ovary were fertilized and the origin and nature of the substances which constitute the fertilization membrane and the substance present in the perivitelline space were traced. In this respect, species differences were found. 6. 6. Precursors were added to a suspension of eggs or embryos for varying lengths of time, and at various stages. No incorporation is obtained in mature unfertilized eggs after 30 minutes' incubation. Incorporation of 14C, although weak, is obtained in eggs immediately after fertilization, whereas incorporation of 35SO 4 is first noticeable only at blastula stage. 7. 7. Added 35SO 4 was incorporated into the blastocoelic gel. Parallel staining with Hale reagent showed that in earlier stages the SO 4-group of the acid polysaccharides contained in this gel are unmasked. From 9–10 hours after fertilization, an incorporation of labeled amino acids into blastocoelic gel was found. At the same time the Hale staining disappeared, indicating masking of the SO 4-groups by proteins. 8. 8. It was demonstrated that, from a period immediately preceding the mesenchyme blastula stage, the incorporation of labeled amino acid becomes more intense in the vegetal region. At the same time the incorporation of 35SO 4 becomes demonstrable. The incorporation of both kinds of labeled precursors has, in the mesenchyme blastula and the early gastrula, its maximum in a region bordering the vegetal region of the blastocoel. 9. 9. The mesenchyme cells are imbedded in a matrix of sulfated polysaccharides combined with proteins. The importance of such a matrix for the formation of filopodial projections is pointed out. 10. 10. In the gastrula stage a parallel incorporation of labeled amino acids and of 35SO 4 was observed in mesenchyme and endomesoderm. The Hale staining indicated, however, that in the mesenchyme connected with the animal region of the ectoderm the sulfate of the acid polysaccharides is masked by proteins. In the mesenchyme connected with the vegetal region of the ectoderm the sulfate is unmasked, not being closely linked to proteins. This latter holds true also for the acid polysaccharides present in the exterior and interior border of the intestine. 11. 11. The RNA available to Hale and pyronin staining is considered to be a low-polymer RNA. This is formed in the outer rim of the nucleolus (cf. p. 361), but also in the most animal region of the developing late blastulae or gastrulae. The possibility is mentioned that the animal region of the larva may be the main site of production of low-polymer RNA. 12. 12. The parallel incorporation of 35SO 4 and 14C-labeled amino acids is considered to suggest that acid polysaccharides may have an acceptor function in protein synthesis. This function would involve a removal of proteins from their site of formation on RNP-particles, favoring the synthesis of new protein molecules. The suggestion is also made that unmasked acid polysaccharides may have an ion-exchange effect which would be important for the control of diffusion of certain substances.

Influence of temperature on the Raman spectra of crystals

The Raman spectrum of barytes excited by the λ2536 radiation of the mercury arc has been studied at a series of eight temperatures ranging from 85° to 923°K., and data furnished regarding the variations in frequency shift and the width of the principal Raman lines. With increasing temperature a definite decrease in frequency shift is observed, the rate of decrease being greater at higher temperatures. While at low temperatures the internal frequencies of the SO4 ion are clearly split up into distinct components, these tend to coalesce as the temperature is increased. The lattice oscillations are observed to be much more temperature sensitive than the internal oscillations of the SO4 group. The 89 cm.−1 lattice line and the 648 cm.−1 internal frequency are comparatively the least affected by temperature variations.

Crystal Structure and the Magnetic Anisotropy of CuSO4.5H2O

FROM a discussion of the magnetic susceptibilities of CuSO4.5H2O powder at different temperatures, Jordahl1 concluded that the crystalline electric field acting on the Cu++ ion in the crystal should be predominantly cubic in symmetry, and further, from the sign of the potential due to this field which fits the magnetic data, that the field should correspond to an octahedral distribution of six equal negative charges around the Cu+ + ion. This result is not obvious from general structural considerations, since the crystal is triclinic, and there are five molecules of water and one SO4 group associated with each Cu+ + ion. The result, however, has been beautifully verified by the X-ray studies of Beevers and Lipson2 on the structure of the crystal. The Cu+ + ion is found to be at the centre of an octahedron of six negatively charged oxygen atoms. Four of them belong to four water molecules, and they form a square with the Cu+ + ion in the centre. The other two, which are contributed by two sulphate groups, are located centrally above and below this square.