Hoffman

Reagent = SOCI2, AC2O, P2O5 or PPA Chem Rev 33 242 (1943) (review) 

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Chemisoq)tion bonding to metal and metal oxide surfaces has been treated extensively by quantum-mechanical methods. Somoijai and Bent [153] give a general discussion of the surface chemical bond, and some specific theoretical treatments are found in Refs. 154-157 see also a review by Hoffman [158]. One approach uses the variation method (see physical chemistry textbooks) ... 

Chuang T J, Hoffman G Wand Eisenthai K B 1974 Piooseoond studies of the oage effeot and ooiiision induoed predissooiation of iodine in iiquids Chem. Phys. Lett. 25 201... 

Kouri D J, Huang Y, Zhu W and Hoffman D K 1994 Variational principles for the time-independent wave-packet-Schrddinger and wave-packet-Lippmann-Schwinger equations J. Chem. Phys. 100... 

Parks E K, Welller B H, Bechthold P S, Hoffman W F, NIeman G C, Pobo L G and Riley S J 1988 Chemical probes of metal cluster structure reactions of Iron clusters with hydrogen, ammonia and water J. Chem. Rhys. 88 1622... 

Bohren C F and Hoffman D R 1983 Absorption and Scattering of Light by Smaii Particies (New York Wiley)... 

Hoffman s extended Huckel theory, EHT (Hoffman, 1963), includes all bonding orbitals in the secular matrix rather than just all n bonding orbitals. This inclusion increases the complexity of the calculations so that they are not practical without a computer. The basis set is a linear combination that includes only valence orbitals... 

For Woodward-Hoffman allowed thermal reactions (such as the conrotatory ring opening of cyclobutane), orbital symmetry is conserved and there is no change in orbital occupancy. Even though bonds are made and broken, you can use the RHF wave function. 

For many reasons, including the Woodward-Hoffman rules that describe the likelihood of reaction based on arguments about the shapes of orbitals, it is desirable to be able to visualize molecular orbitals. 

Hoechst slurry process Hoeppler viscometer Hoffman degradation Hoffman eliminations Hofmann degradation... 

Hoffman Degradation. Polyacrylamide reacts with alkaline sodium hypochlorite [7681-52-9], NaOCl, or calcium hypochlorite [7778-54-3], Ca(OCl)2, to form a polymer with primary amine groups (58). Optimum conditions for the reaction include a slight molar excess of sodium hypochlorite, a large excess of sodium hydroxide, and low temperature (59). Cross-linking sometimes occurs if the polymer concentration is high. High temperatures can result in chain scission. 

W. J. Budant and A. S. Hoffman, Block and Graft Polymers, Reinhold Puhhshing Corp., New York, 1960. 

H. J. Hoffman, Moisture Effects on Mechanical Properties of Solid Propellants, CPTR 84-29, CPIA Pubhcations, Johns Hopkins University, Laurel, Md., Feb. 1984. 

C. J. Hoffman, Phosphorus—Fluorine Oxidi rs, PF-150613-1, Part 7, Propulsion Chemistry Part II, Lockheed Aircraft Corp., Missiles and Space Div., Burbank, Calif., 1959. 

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