@article {4134,
	title = {Muonium reactions with oxalic acid and oxalate ions in water: Huge kinetic isotope effects when compared with H},
	journal = {Journal of Physical Chemistry A},
	volume = {101},
	number = {13},
	year = {1997},
	note = {ISI Document Delivery No.: WQ630Times Cited: 1Cited Reference Count: 20},
	month = {Mar},
	pages = {2442-2444},
	type = {Article},
	abstract = {The reactions of muonium atoms with the individual species HO2CCO2H, HO2CCO2-, and -O2CCO2- at similar to 295 K in water have absolute bimolecular rate constants of 5.6, 0.71, and 0.054 x 10(8) M(-1) s(-1), respectively. No such 100-fold pH-dependence has hitherto been seen for muonium, although H and e(aq)(-) also show large pH effects in reactions with oxalic acid. Arrhenius plots for the muonium reactions at pH = 1, 3, and 8 show the unusually small activation energies of less than or equal to 17 kJ/mol for all three acid-base forms of oxalic acid. When the reaction rate of muonium is compared with published data on ordinary H atoms at pH = 1 (57\% oxalic acid and 43\% hydrogen oxalate ions), one obtains a kinetic isotope effect of 850 favoring muonium. For the dianion at pH greater than or equal to 7, the muonium-to-H rate ratio is >300, These seem to be the largest primary kinetic isotope effects ever reported. The reaction is taken to be addition of muonium to one of the C=O groups, and the large isotope effect and small E(a) suggest considerable contributions from quantum mechanical tunneling.},
	keywords = {AQUEOUS-SOLUTIONS, HYDROGEN-ATOMS, radicals},
	isbn = {1089-5639},
	url = {<Go to ISI>://A1997WQ63000011},
	author = {Stadlbauer, J. M. and Barnabas, M. V. and Walker, D. C.}
}
