Characterization, kinetics and mechanisms of electron transfer reactions of superoxochromium (III) ion and a cobalt (II) macrocyclic complex with various substrates

The cation (H[subscript]2O)[subscript]5CrO[subscript]2[superscript]2+ has a considerable lifetime in aqueous solution in the absence of Cr[superscript]2+. One pathway for decomposition consists of bond homolysis, CrO[subscript]2[superscript]2+ → Cr[superscript]2+ + O[subscript]2. The resulting Cr[superscript]2+ then reacts very rapidly with CrO[subscript]2[superscript]2+. A second pathway, yielding HCrO[subscript]4[superscript]-, proceeds by a bimolecular reaction between two CrO[subscript]2[superscript]2+ ions. The data do not require a description of CrO[subscript]2[superscript]2+ as other than a superoxochromium(III) ion;The oxidation-reduction reactions of the superoxochromium(III) ion have been examined with several well-known one electron reducing agents, Ru(NH[subscript]3)[subscript]6[superscript]2+, Co(sep)[superscript]2+, and V(OH[subscript]2)[subscript]6[superscript]2+. The results are consistent with outer-sphere mechanisms. Studies were also carried out with several mild reducing agents with labile coordination positions, Fe(OH[subscript]2)[subscript]6[superscript]2+, Co((14) aneN[subscript]4)(OH[subscript]2)[subscript]2[superscript]2+, and Co((15) aneN[subscript]4)(OH[subscript]2)[subscript]2[superscript]2+. The results are consistent with inner-sphere mechanisms characterized by the formation of a binuclear intermediate and subsequent decomposition of this intermediate;The cobalt(II) macrocycle L[subscript]2Co(dmgBF[subscript]2)[subscript]2 has been characterized by crystallography (L = CH[subscript]3OH) and by spectroscopic UV/vis, EPR, electrochemical, and magnetic methods as well as elemental analysis for L = H[subscript]2O. In aqueous perchloric acid the diaquo complex is reversibly oxidized to (H[subscript]2O)[subscript]2Co(dmgBF[subscript]2)[subscript]2[superscript]+ by Fe[superscript]3+. The equilibrium constant was determined for this reaction yielding the reduction potential for the Co(III)/Co(II) couple. The prominent inverse-(H[superscript]+) component suggests an inner-sphere reaction between (H[subscript]2O)[subscript]2FeOH[superscript]2+ and the Co(II) complex. A detailed analysis of the mechanism interpreted on that basis is presented; it suggests that intramolecular electron transfer within a binuclear intermediate is the rate limiting step;The characterization, kinetics, and mechanisms of the reactions of (H[subscript]2O)[subscript]2Co(dmgBF[subscript]2)[subscript]2 with various oxidants were studied in aqueous solution. The reaction of (H[subscript]2O)[subscript]2Co(dmgBF[subscript]2)[subscript]2 with hydrogen peroxide follows a 1:1 reaction stoichiometry ((H[subscript]2O)[subscript]2Co(dmgBf[subscript]2)[subscript]2:H[subscript]2O[subscript]2). This reaction has a complex mechanism which includes the oxidation of the Co(II) metal center as a first stage. The reaction of (H[subscript]2O)[subscript]2Co(dmgBF[subscript]2)[subscript]2 with t-BuOOH follows a 2:1 reaction stoichiometry ((H[subscript]2O)[subscript]2Co(dmgBF[subscript]2)[subscript]2:t-BuOOH). The mechanism for this reaction includes the formation of (H[subscript]2O)[subscript]2Co(dmgBF[subscript]2)[subscript]2[superscript]+ and CH[subscript]3Co(dmgBF[subscript]2)[subscript]2(H[subscript]2O). ftn[superscript] aDOE Report IS-T-1297. This work was performed under contract No. W-7405-Eng-82 with the U.S. Department of Energy.</p

Sandia National Laboratories, California Chemical Management Program annual report.

The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Chemical Management Program. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. This program annual report describes the activities undertaken during the calender past year, and activities planned in future years to implement the Chemical Management Program, one of six programs that supports environmental management at SNL/CA. SNL/CA is responsible for tracking chemicals (chemical and biological materials), providing Material Safety Data Sheets (MSDS) and for regulatory compliance reporting according to a variety of chemical regulations. The principal regulations for chemical tracking are the Emergency Planning Community Right-to-Know Act (EPCRA) and the California Right-to-Know regulations. The regulations, the Hazard Communication/Lab Standard of the Occupational Safety and Health Administration (OSHA) are also key to the CM Program. The CM Program is also responsible for supporting chemical safety and information requirements for a variety of Integrated Enabling Services (IMS) programs primarily the Industrial Hygiene, Waste Management, Fire Protection, Air Quality, Emergency Management, Environmental Monitoring and Pollution Prevention programs. The principal program tool is the Chemical Information System (CIS). The system contains two key elements: the MSDS library and the chemical container-tracking database that is readily accessible to all Members of the Sandia Workforce. The primary goal of the CM Program is to ensure safe and effective chemical management at Sandia/CA. This is done by efficiently collecting and managing chemical information for our customers who include Line, regulators, DOE and ES and H programs to ensure compliance with regulations and to streamline customer business processes that require chemical information

Sandia National Laboratories, California Hazardous Materials Management Program annual report : February 2009.

The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Hazardous Materials Management Program. It functions as supporting documentation to the SNL/CA Environmental anagement ystem Program Manual. This program annual report describes the activities undertaken during the past year, and activities planned in future years to implement the Hazardous Materials Management Program, one of six programs that supports environmental management at SNL/CA

Sandia National Laboratories, California Chemical Management Program annual report.

The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Chemical Management Program. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. This program annual report describes the activities undertaken during the calender past year, and activities planned in future years to implement the Chemical Management Program, one of six programs that supports environmental management at SNL/CA. SNL/CA is responsible for tracking chemicals (chemical and biological materials), providing Material Safety Data Sheets (MSDS) and for regulatory compliance reporting according to a variety of chemical regulations. The principal regulations for chemical tracking are the Emergency Planning Community Right-to-Know Act (EPCRA) and the California Right-to-Know regulations. The regulations, the Hazard Communication/Lab Standard of the Occupational Safety and Health Administration (OSHA) are also key to the CM Program. The CM Program is also responsible for supporting chemical safety and information requirements for a variety of Integrated Enabling Services (IMS) programs primarily the Industrial Hygiene, Waste Management, Fire Protection, Air Quality, Emergency Management, Environmental Monitoring and Pollution Prevention programs. The principal program tool is the Chemical Information System (CIS). The system contains two key elements: the MSDS library and the chemical container-tracking database that is readily accessible to all Members of the Sandia Workforce. The primary goal of the CM Program is to ensure safe and effective chemical management at Sandia/CA. This is done by efficiently collecting and managing chemical information for our customers who include Line, regulators, DOE and ES and H programs to ensure compliance with regulations and to streamline customer business processes that require chemical information

Sandia National Laboratories, California Hazardous Materials Management Program annual report.

The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Hazardous Materials Management Program. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. This program annual report describes the activities undertaken during the calender past year, and activities planned in future years to implement the Hazardous Materials Management Program, one of six programs that supports environmental management at SNL/CA

Sandia National Laboratories, California Waste Management Program annual report : February 2009.

The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Waste Management Program. It functions as supporting documentation to the SNL/CA Environmental Management System rogram Manual. This annual program report describes the activities undertaken during the past year, and activities planned in future years to implement the Waste Management (WM) Program, one of six programs that supports environmental management at SNL/CA