James Fresco

Infrared Spectra of Divalent Metal Monothioacetylacetonates

The infrared spectra of copper (II), nickel (II), zinc (II), palladium (II), cadmium (II), and lead (II) complexes of monothioacetylacetone have been recorded from 1700–300 cm−1. Assignments for in‐plane vibrations were obtained by normal coordinate analyses. The carbon–oxygen stretching vibration was located near 710 cm−1. In every case metal–oxygen stretching force constants were larger than metal–sulfur constants and carbon–sulfur constants were less than carbon–oxygen constants. Systematic trends which appeared among both metal–sulfur and metal–oxygen stretching force constants were correlated with sequences observed among the carbon–donor atom force constants.

Solvent extraction of trialkylammonium salts

Abstract Partition constants have been determined for a series of trialkylammonium chlorides, bromides, iodides and perchlorates between water and nitrobenzene. Extraction of these salts into nitrobenzene increases in the order Cl - - - 4 - . The extraction constant for salts with the same anion increases with increasing chain length of the ammonium ion from tripropyl to trihexyl. An electrostatic model of the Borncharging type was not sufficient to predict transfer equilibrium constants of the dissociated ions.

Infrared Spectra of Divalent Metal Trifluoromonothioacetylacetonates

The infrared spectra of the metal chelates of trifluoromonothioacetylacetone with nickel (II), zinc (II), palladium (II), cadmium (II), and lead (II) have been recorded over the range 1700–300 cm−1. Frequencies and force constants of in‐plane vibrations in these chelates were determined by normal‐coordinate analyses. Assignments of the metal–ligand vibrations were supported by the infrared spectrum of the dipyridine adduct of bis (trifluoromonothioacetylacetonato) nickel (II). Out‐of‐plane, methyl group and trifluoromethyl group normal modes were assigned by reference to structurally similar compounds. The influence of the strongly electron‐withdrawing group, –CF3, on the chelate ring is discussed.

Iridium in sea-water.

Iridium in sea-water has been measured (after isolation from the saline matrix by reduction with magnesium) by neutron bombardment, radiochemical purification and high-resolution gamma-ray spectroscopy. The concentration obtained in a Pacific coastal water was 1.02 +/- 0.26 x 10(-14) g per g of sea-water. At such extremely low concentrations, seawater is an extremely unlikely source for anomalously high iridium concentrations measured in the Cretaceous-Tertiary boundary layer of deep-sea sediments.

Conductometry of nitrobenzene solutions of trialkylammonium salts

Abstract The conductance of water-saturated nitrobenzene solutions of unbranched trialkylammonium salts has been measured. Dissociation constants of the salts decrease in the order; perchlorate, iodide, bromide, and chloride. Dissociation does not appear to increase with increasing alkyl chain length.

Vibrational spectrum of 1,3,5,7-tetramethyl-2,4,6,8-tetrathiaadamantane

Abstract The infrared and Raman spectra of the dimer of dithioacetylacetone, 1,3,5,7-tetra-methyl-2,4,6,8-tetrathiaadamantane, have been recorded over the ranges 4000–100 cm −1 and 4000–100 cm −1 , respectively. Vibrational assignments were determined by a normal coordinate analysis. The vibrational frequencies and force constants obtained have been compared with those of compounds of similar structure.