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The far-infrared spectra of platinum(IV) complexes of the types cis- and trans-[PtX4L2](X = Cl, Br, or I; L = donor ligand) are assigned and discussed. For the trans complexes the halogen-sensitive modes occur near those of the related [PtX4]2– species whilst the ν(Pt–X) pattern for the cis complexes covers a wide range which includes that of ν(Pt–X) in bridging situations in platinum(II) compounds. Assignments are given for ν(Pt–P), ν(Pt–As), ν(Pt–S), and for the associated bending modes.

Raman and far-i.r. spectra are reported and assigned for the solid complexes Cr(CO)3(π-arene)(arene = benzene, aniline, toluene, methyl benzoate, anisole, and hexamethylbenzene) and M(CO)3(π-mesitylene)(M = Cr, Mo, or W). For the benzene complex, discussion is based upon the factor group, but in the other cases the molecular point-symmetry proves to be an adequate approximation. C3v local symmetry is an inadequate approximation when discussing the skeletal modes of complexes of monsubstituted arenes.

Exposure of Bacillus subtilis A spores to 115 to 125 C for several seconds activated a low-temperature germination system that remained dormant after a heat treatment that activated the normal l -alanine- and glucose-stimulated germination systems. The low-temperature germination system was characterized by an optimum temperature lower than that of the l -alanine or glucose germination systems (30 C versus 45 C), germination in the absence of exogenous germination stimulants, and the capacity for heat-induced deactivation and subsequent reactivation. The rates of activation at 115 to 125 C were exponential and were not influenced by a previous heat treatment that activated the l -alanine- or glucose-stimulated germination systems. Although activation of the low-temperature germination system was accompanied by suppression of l -alanine-stimulated germination, it did not appear to be a modification of the l -alanine germination system.

Raman and i.r. spectra of the title compounds are reported and assigned for both solids and solutions. ν(C–H) modes show correlationsplitting, but the remainder of the internal modes of the π-allyl ligands can be discussed in terms of Cs local symmetry. ν(C–C–C) modes of the allyl skeleton are placed ca. 1383 and 1020 cm.–1 in the parent complex.

This article1 was originally planned as a brief report on a survey carried out amongst the 1970 class of graduates in social work at the University of Queensland. I was prompted to explore some of the factors involved in the graduates' choices of employment after having had discussions with the head of one of the State Government agencies in Brisbane. The agency head felt that he was not able to recruit new graduates because of the well-known workload carried by social workers in the agency, and because of the attractions of the bright lights of Sydney and Melbourne.

The O—H stretching frequency for methanol in the system methanol + dichloromethane + tetra-alkylammonium perchlorate is almost equal to that for a band which appears when perchlorate salts are dissolved only in methanol. The band is therefore assigned to methanol molecules hydrogen-bonded to perchlorate anions. A band which appears in the spectrum of HOD in H2O when perchlorates are added is, by analogy, similarly assigned. Other arguments against a previous theory that, for aqueous solutions, this band is due to free OD groups, are advanced. The influence of the cation upon the band for solvent molecules not associated with perchlorate ions is discussed.

A new design of diamond anvil high pressure cell suitable for use in infrared and Raman spectroscopy is described. Its performance is demonstrated with particular reference to the pressure dependence of the infrared spectrum of K2PtCl6 and the Raman spectrum of W(CO)6. In contrast to earlier reports, in which forward scattering geometry was used, this design of cell is shown to be very suitable for Raman use in the 180° excitation mode. However, severe limitations are imposed by the fluorescence emission of diamond and of sapphire. Conditions under which the cell can be used for Raman work are summarized. New fluorescence and Raman features are reported for diamond. In particular, a band at 1730 cm−1 is characteristic of type I stones and may be due to C to N bond stretching at defect centers.

The far-infrared spectra (70–400 cm.–1) of 36 thiourea and ethylenethiourea (imidazolidine-2-thione) complexes, embracing several different stereochemical types, are assigned and discussed. Metal–sulphur stretching frequencies, v(M–S), lie in the range 298–205 cm.–1 for the transition-metal complexes, and vary with co-ordination number and electron configuration in the manner now familiar from the behaviour of metal–hylogen stretching frequencies, v(M–X). For Group metals v(M–S) has been found as low as 170 cm.–1. The similarity between the spectra of thiourea complexes and those of thiocyanates has led to an assignment of the published data for thiocyanates. Some interesting variations in halogen-sensitive vibrations have been encountered.

I.r. spectra (70–4000 cm.–1) of nickel complexes of the type [Ni(S2C2R2)2]n–(R = H, CF3, or CN) and of [M(S2C2(CN)2)2]n–(M = Co, Cu, Zn, Pd, or Pt) are discussed. Vibrations containing a large (ν(M–S) contribution are found in the range 465–295 cm.–1. Frequency and intensity variations are consistent with the molecular orbital description of the bonding.For dithiophosphate complexes of three types of stereochemistry ν(M–S) is assigned in the region 330–220 cm.–1; the variation is mainly due to the differing masses of the metal.These results, together with other published work, lead to correlations for ν(M–S) for various ligands in the range 504–205 cm.–1.

Raman single-crystal spectra are reported for eight hydrates and deuteriates [MCl5(H2O)]2–(M = In or Fe). Many fewer lattice modes were found than predicted, but for the anion internal modes factor-group predictions accord well with observation. A complete assignment in terms of anion C4v symmetry is deduced. Deuteriation enabled identification of all skeletal modes associated with oxygen-atom motions. The most unusual feature of the assignments is that π(MCl4) modes come above δ(MCl4) modes. Comparison with single-crystal assignments for [InCl5]2– show that the largest change is in the A1π(InCl4) mode which is raised upon aquation of the complex.

The far-infrared spectra of some halogenocuprates of the types [CuX4]2–(planar and tetrahedral), [Cu2X6]2–, CsCuX3, and M2ICuCl4,2H2O have been studied. Complexes of the type CuX2L2(X = Cl or Br; L = donor ligand) are also considered. v(Cu–Cl) lies in the range 368—222 cm.–1 and v(Cu–Br) between 278 and 168 cm.–1. The spectra admit of a consistent interpretation without the need to postulate the presence of v(Cu–X) modes in the normal region due to stretching of copper–halogen “long” bonds. Bridging v(Cu–X) frequencies have been assigned but the range is severely overlapped by that of terminal v(Cu–X).

Clostridium perfringens spores (three strains) were normally resistant to germination by lysozyme. In the absence of disulfide bond-breaking reagents, tetrasodium ethylenediaminetetraacetate rapidly sensitized the spores to lysozyme.

The ν(CO) spectra of Mo(CO)4 bipy (bipy = 2,2′-bipyridyl), cis-[W(CO)2{o-C6H4(PEt2)2}2],Cr(CO)3(π-mesitylene), and Cr(CO)3(π-C6H5·CO2Me) are examined in solution in n-hexane–chloroform or –nitrobenzene mixtures; the ν(NO) spectrum of Fe(NO)(S2CNMe2)2 is studied in benzene–nitromethane mixtures. Structure observed on the ν(CO) bands is discussed in terms of formation of solvent–solute complexes.

Raman and i.r. spectra are reported and assigned for X2Sn[Co(CO)4]2,X2Sn[Fe(CO)2(π-C5H5)]2(X = Cl, Br, and I), and M-SnCl3, (M = Mo(CO)3(π-C5H5); Rh(NBD)2; Ir(COD)2), and for a number of related compounds. Metal–metal stretching frequencies are in the range 165–235 cm.–1 and are intense in the Raman spectra.

Clostridium perfringens strain NCTC 8798 spores were injured by ultrahigh temperature treatment and were unable to outgrow in the presence of antibiotics used in selective enumeration media. Injured spores underwent repair in a nonselective laboratory medium and in foods.

Vibrational frequencies and force constants are reported for the ions [MCl6]2–(M = Ti, Zr, or Hf). An error in the early literature is corrected.

Hock and Stuhlman1 discovered that the reaction of iron pentacarbonyl with mercuric halides yielded solid products, which they formulated as addition compounds Fe(CO)4Hg·(HgX2), containing the Fe(CO)4Hg moiety which itself can be obtained by reaction of iron pentacarbonyl and mercuric sulphate. No structural information on these compounds is available, although Wells2 has suggested that Fe(CO)4Hg is polymeric and trans.

All the Raman-active modes of [Fe(CN6)]3– have been observed in aqueous solution. For single-crystals (ambient and ca. 160 K) the predictions of factor-group analysis are largely borne out by experiment, as is most of the Raman spectrum calculated by Nakagawa and Shimanouchi. Bonding in the crystal is discussed.

Raman and far-i.r. spectra for single crystals of tetrakis(thiourea)nickel(II) dichloride have been obtained at ca. 120 K and at ambient temperature. The results allow unambiguous assignment to A, B, and E species (in C4 symmetry). Descriptions of many of the internal modes are also offered.

Vibrational spectra of the ions [MCl6]2–(M = Cr, Mn, Fe, In, or lr) and [MCl6]3–(M = Mn or Ce) are assigned. The ν3 values show the effect of the differences in electronic structure of the metal atoms, being very low for M = Fe (t2g3eg2) and high for M = MnIII(Jahn–Teller distorted). Further spectra of tetrahalogenothallates are reported and show some differences at low frequencies from those previously published.