A method for the analysis of commercial Inorganic ollgophosphates has been developed based on the use of hlghresohitlon phosphorus-31 Fourier transform nuclear magnetic resonance (NMR). Experimental parameters were selected to optimize accuracy, precision, and analysis time. The accuracy and precision of the NMR method have been demonstrated to be comparable to chromatographic methods and superior to IR and XRD In controlled Interlaboratory analyses using commercial sodium tripolyphosphate. This study represents the only thorough and direct comparison of methods for phosphate species analysis. The major source of error In the NMR method Is In obtaining reproducible Integrations for signals with proximate chemical shifts, but the precision may be greatly Improved using a line-shape analysis and curvefitting routine. Detection limits of 1-10 mg P/L may be attained with phosphorus-31 NMR by scanning overnight.

The photochemical reaction of Re2(CO)10 with H20 in THF and other solvents has been studied, with use of radiation of varying wavelength. The initial reaction leads to Re2(CO)9(OH2), formed upon irradiation at 313 nm. This product is shown to form via a primary photochemical homolysis of the Re-Re bond, followed by thermal substitution of the Re(CO)5radical by H20, and then re-formation of the metal-metal bond to give Re2(CO)9(OH2). Although Re2(CO)9(OH2) is relatively stable toward 313-nm irradiation, it decomposes rapidly under 366-nm irradiation to form HRe(CO)5 and Re4(CO)12(OH)4. The decomposition pathway is thought to involve Re2(CO)8(OH2)2, an unstable intermediate. The presence of this intermediate is substantiated in part by the observation that thermal reaction of Re2(CO)8(CH3CN)2 with H20 in THF leads to formation of Re4(CO)12(OH)4. The decomposition of Re2(CO)8(OH2)2 is proposed to proceed via initial loss of H20 and oxidative addition of an O-H bond to form (µ-hydrido)^-hydroxo)dirhenium octacarbonyl, HRe2(CO)8(OH), which undergoes decomposition to form the observed products.

Hexane solutions of Mn2(CO)10 and Re2(CO)10 have been subjected to flash photolysis. Under 1 atm of CO pressure, the absorbance due to the dinuclear species returns to the original value in accordance with a simple bimolecular rate law. This behavior suggests that the only process of importance in the solutions is bimolecular recombination of M(CO)s• radicals.The bimolecular rate constants obtained at 22 °C are kt = 9.5 X 108 M'1 s'1 for Mn2(CO)10 and 3.7 X 109 M'1 s'1 for Re2(CO)10. When the solutions are thoroughly degassed prior to flash photolysis, a more complex behavior is noted. Intermediates that are more strongly absorbing in the 350-500-nm region than the M2(CO)10 species are formed and then disappear over a period

Most commercial applications of phosphorus‐containing materials are based on phosphoric acids and the phosphates. Uses, other than as fertilizer, include applications in detergency, foods and food processing, dental materials, dentifrices, metal surface treatments, flame retardency, etc. Structures and properties of orthophosphoric acid and condensed phosphoric acids are presented. The manufacture of technical‐ and food‐grade phosphoric acids by thermal and wet acid purification processes, as well as some of the uses of the various phosphoric acids, are discussed. The chemistry and properties of orthophosphates and condensed phosphates are presented. Emphasis is placed on alkali metal and calcium salts and their solution properties. Properties specific to condensed phosphate salts such as hydrolysis and metal ion complexation are outlined. Manufacturing schemes for the phosphates are described and attention is given to the control of product properties.

Most commercial applications of phosphorus‐containing materials are based on phosphoric acids and the phosphates. Uses, other than as fertilizer, include applications in detergency, foods and food processing, dental materials, dentifrices, metal surface treatments, flame retardency, etc. Structures and properties of orthophosphoric acid and condensed phosphoric acids are presented. The manufacture of technical‐ and food‐grade phosphoric acids by thermal and wet acid purification processes, as well as some of the uses of the various phosphoric acids, are discussed. The chemistry and properties of orthophosphates and condensed phosphates are presented. Emphasis is placed on alkali metal and calcium salts and their solution properties. Properties specific to condensed phosphate salts such as hydrolysis and metal ion complexation are outlined. Manufacturing schemes for the phosphates are described and attention is given to the control of product properties.