... and alkaline-earth cations and the high degree of hydration. The process of eudialyte decationization is accompanied by hydration, and hydrous species are incorporated into the mineral structure predominantly as H 3 O-groups. Those oxonium groups act as monovalent cations, replacing alkaline and alkaline-earth...

...Wolfram W. RUDOLPH; Roger MASON; Peer SCHMIDT Abstract Stoichiometric end-member alunites of the general formula (A)Al 3 (SO 4 ) 2 (OH) 6 , with A = Na + , K + , Rb + , H 3 O + , and NH 4 + have been synthesized under hydrothermal conditions together with samples of the potassium-oxonium solid...

...George A. Lager; Gregg A. Swayze; Chun-Keung Loong; Frank J. Rotella; James W. Richardson, Jr.; Roger E. Stoffregen Abstract Synthetic, polycrystalline samples of alunite [K 0.88 (H 3 O) 0.12 Al 2.64 (SO 4 ) 2 (OH) 4.92 (H 2 O) 1.08 ] and oxonium-substituted alunite [H 3 OAl 2.87 (SO 4 ) 2 (OH...

...Ronald W. T. Wilkins; Abdul Mateen; Geoff West Abstract Nuclear magnetic resonance(NMR)and infrared spectroscopic studies of some mineral species in which the presence of oxonium ions has been postulated show that it is often difficult to obtain direct evidence of their existence. Clear evidence...

... all the known uranate minerals. The replacement of water is interpreted by postulating presence of oxonium and X m 2 + ( H 3 O ) 2 − m + [ ( UO 2 ) 2 O 2+m ( OH ) 2 − m ] X m 2 + ( H 3 O ) 2 − m + [ ( UO 2 ) 2 O ( OH ) ] 2 A structure model is proposed in which X ++ , X + , H 3 O + are interlayer...

... 3 O + , K + , and NH 4 + over the water molecules sites observed in the abernathyite-like compounds may be a common feature of the interlayer structure of the hydrous layer silicates and of the intercage structure of the zeolites and clathrate compounds. The specia-nature of the oxonium ion...

... are discussed. The smallest monovalent cation, Li, occurs in tetrahedral coordination between fourfold squares of hydrogen-bonded H 2 O groups. Despite a wide range in ionic radius, Na, K, Rb, Ag and Tl randomly substitute for H 2 O groups in the interlayer, in the same fashion as their ammonium and oxonium...

..., however, indicate that this “water” is best represented as oxonium ions (H 3 O + ) formed by interaction of the 12-coordinated interlayer H 2 O molecules with certain octahedral-layer hydroxyl groups according to the relation: H 2 O + OH − → H 3 O + + O 2 − or [ ( H 2 O ) 2 XII Mg 6 VI Si 8 VI O 20 ( OH...

...) = 1.09] disappears if H + , which is 0.3737 ions per formula in excess of that required by an ideal 8H 2 O in the unit cell, is present as oxonium ion. Thermogravimetric analysis gives good agreement with TGA curves from the type locality. Ion-exchange values determined show a low-exchange capacity...

.... A deficiency of bases is believed to be compensated for by oxonium H 3 O (super +) ions. The natroalunite is believed to have developed under oxidizing conditions, with pyrite as the source of the SO 4 . Experiments suggest its derivation to be from aluminite. GeoRef, Copyright 2008, American Geological...

... an oxonium ion, and three water molecules are distributed randomly over four H 2 O sites. To express this distribution of cations over water molecule sites the structural formulas of phases (I), (II), and (III) are written (K · 3H 2 O) (UO 2 ASO 4 ), [(NH 4 )·3H 2 O](UO 2 AsO 4 ), and [ K 1 2 ( H 3 O ) 1 2...