Fumio Watari

Infra-red absorption spectra of charge-transfer complexes of trimethylamine: (CH3)3N·I2, (CH3)3N·IBr and (CH3)3N·ICl

Abstract The infra-red spectra of (CH 3 ) 3 N·IX, where X is I, Br or Cl, have been studied in the 4000-60 cm −1 region. Assigmnents of the fundamentals have been made.

Vibrational spectra of (CD3)4M, and normal coordinate calculations for (CH3)4M and (CD3)4M (M = Si, Ge, Sn, Pb)

Abstract Vibrational spectra of (CD 3 ) 4 M (M = Si, Ge, Sn, Pb) in the gas phase (i.r.) and in the liquid state (Raman) have been obtained, and assignments of all the fundamentals presented. The complete symmetry coordinates for the ( X Y 3 ) 4 Z type molecule of T d symmetry have been offered and normal coordinate calculations carried out by a symmetry force field treating the two isotopic species, (CH 3 ) 4 M-d 0 and —d 12 , simultaneously.

Far infra-red spectra of pyridine—iodine monochloride and pyridine—iodine monobromide complexes

Abstract The far infra-red spectra of pyridine—iodine monochloride and pyridine—iodine monobromide complexes have been measured in the region from 500 cm −1 to 80 cm −1 in paraffin mulls. Three absorption bands were observed and assigned as py·ICl; ν 16 b (pyridine) = 425 cm −1 , ν ICl = 265 cm −1 , ν NI = 170 cm −1 : py·IBr; ν 16 b (pyridine) = 421 cm −1 , ν IBr = 200 cm −1 , and ν NI = 160 cm −1 . Under assumptions of a linear triatomic model and ƒ NI,ICl = ƒ NI,IBr , the force constants were calculated: ƒ ICl = 1·18 (estimated by the Badgers rule), ƒ IBr = 1·05, ƒ NI(CI) = 0·91, ƒ NI(Br) = 0·85, and ƒ NI,ICl = ƒ NI,IBr = 0·22 (mdyn/A). The force constant of the interhalogen vibration, ƒ IX is one half of that of the free molecule. The interaction constant is larger than that of a usual molecule, which will be characteristic of the molecular complex.

Vibrational spectra of (CD3)3MX and normal coordinate calculations for (CH3)3MX and (CD3)3MX (M = Ge, Sn; X = Cl, Br)

Abstract IR (4000-30 cm−1) and Raman (4000-0 cm−1) spectra of (CH3)3MX (M = Ge, Sn; X = Cl, Br) have been recorded, together with those of (CD3)3MX. By assuming the C3v, molecular symmetry, all the active fundamentals except an internal torsion have been assigned and normal coordinate calculations have been carried out to confirm the proposed assignments by a symmetry force field for (CH3)3MX and (CD3)3MX.

Normal coordinate analyses of trimethylphosphine oxide, trimethylphosphine sulfide and trimethylphosphine selenide

Abstract The infrared and Raman spectra of trimethylphosphine oxide, trimethylphosphine sulfide, trimethylphosphine selenide and their perdeuterated analogues have been recorded. The fundamentals (except for the internal torsion) have been assigned for each molecule. Normal coordinate calculations were carried out by a symmetry force field to confirm the proposed assignments, and to derive the PO, PS and PSe stretching force constants.

Effect of crystalline properties on coercive force in iron acicular fine particles

Crystallographic properties and their size dependence in acicular fine particles of iron prepared by reduction fromα-FeOOH were investigated by transmission electron microscopy and compared with magnetic properties. Although both larger particles with an average needle length of 0.5μm and smaller ones of 0.2μm length have single domain configuration, the former are crystal lographicaIly polycrystalline while the latter are single crystal with a [100] axial orientation, an easy magnetization direction of iron. The coercive force, principally yielded by external shape anisotropy, is higher in smaller particles in spite of their inferior axial ratio. The intrinsic magnetocrystalline anisotropy is inferred to be the most responsible to give rise to this further increase of coercive force. The experimentally obtained values of magnetic properties are also compared with the theoretical estimation, which results semi-quantitatively in good accordance.

Vibrational spectra and normal coordinate calculations for (CH3)3GECN and (CD3)3GECN

Abstract Infrared spectra of (CH3)3GeCN and (CD3)3GeCN have been obtained over the range of 4000–100 cm−1 from solutions of benzene and dichloromethane, and solid films deposited on windows at liquid nitrogen temperature. Raman spectra have been photographed in dichloromethane solution. Assignments for all fundamentals except the internal torsions have been made, and normal coordinate calculations carried out by a symmetry force field to confirm the proposed assignments.

Hydrogen bonding between phenol and alkyl thiocyanates

Abstract Hydrogen bonding between phenol and alkyl thiocyanates, dissolved in carbon tetrachloride, has been studied by means of infrared spectroscopy. The appearance of a new OH stretching vibration band, about 150 cm −1 lower than that of free phenol, clearly indicates the formation of the hydrogen bond in this system. Using an empirical relation between the concentration of phenol and the intensity of the free OH stretching vibration band, the equilibrium constants have been determined over the temperature range 20–50°C. From these, the heats of bonding (2.9–4.1 kcal mol ) and the entropy changes (7–11 e.u.) have been obtained.

Vibrational spectra and normal coordinate calculations for methylethynylmercury(II)-d0, -d1, -d3, and -d4,

Abstract Infrared spectra (4000-80 cm −1 ) and Raman spectra (4000-O cm −1 ) of methylethynylmercury(II) d 0 , - d 1 , - d 3 , and - d 4 , have been recorded. Assignments for all the fundamentals have been made assuming C 3υ molecular symmetry. Normal coordinate calculations have been carried out.

Vibrational spectra and normal coordinate calculations for (CH3)3AsO and (CD3)3AsO

Abstract Infrared spectra of (CH 3 ) 3 AsO and (CD 3 ) 3 AsO have been obtained over the range of 4000-100 cm −1 from the solid films sublimed on windows at room and at liquid nitrogen temperatures. Raman spectra have been photographed in chloroform and acetonitrile solutions. Assignments for all fundamentals except the internal torsions have been made, and normal coordinate calculations carried out by a symmetry force field to confirm the proposed assigmnents.