Room-temperature reactions of VX, GB, GD, and HD with nanosize Al(2)O(3) (AP-Al(2)O(3)) have been characterized by (31)P, (13)C, and (27)Al MAS NMR. Nerve agents VX, GB, and GD hydrolyze to yield surface-bound complexes of their corresponding nontoxic phosphonates. At sufficiently high loadings, discreet aluminophosphonate complexes, Al[OP(O)(CH(3))OR](3), are generated which are identical to synthesized model compounds. Thus the reaction with phosphonic acids is not just surface-limited, but can continue to the core of alumina particles. HD mainly hydrolyzes at lower loadings to yield thiodiglycol (TG, 71%) and a minor amount of the CH-TG sulfonium ion (12%), although some elimination of HCl is also observed (17%). The reactive capacity for HD is evidently exceeded at high loadings, where complete conversion to TG is hindered. However, addition of excess water results in the quantitative hydrolysis of sorbed HD to CH-TG. On AP-Al(2)O(3) dried to remove physisorbed water, (13)C CP-MAS NMR detects a surface alkoxide consistent with that of TG.

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Reactions of VX, GD, and HD with Al2O3, TiO2 (anatase and rutile), aluminum, and titanium metal powders have been studied by 27Al, 47,49Ti, 31P, and 13C MAS NMR. VX, GD, and HD hydrolyze on both nanosize and conventional Al2O3. A significant droplet size effect on the reaction kinetics is observed. For VX and GD, 27Al and 31P MAS NMR detect the formation of aluminum phosphonate complexes. Similarly, GD hydrolysis on TiO2 yields titanium phosphonate species as detected by 31P MAS NMR. Attempts at obtaining 47,49Ti NMR spectra of these species and those of titanium phosphonate model compounds at 14 T were marginally successful. 47,49Ti NMR spectra were obtainable for anatase and titanium metal; thus, severe second-order quadrupolar linebroadening is suspected for the titanium phosphonate complexes. 47,49Ti NMR spectra obtained for anatase at high magnetic field (17.5 and 21 T) showed anticipated improvement in peak width and resolution. GD reacted with aluminum and titanium powder in the presence of water results in acid-dissolution of the metals and the formation of their respective metal phosphonates.

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