Structure and Bonding of Cu(II)–Glutamate Complexes at the γ-Al2O3–Water Interface

Reaction of aqueous Cu–Citrate with MnO2 birnessite: Characterization of Mn dissolution, oxidation products and surface interactions

“…1A. In the Cu(II)Glutamate reaction with Al 2 O 3 , a 1:2 ratio Type B surface complex with long-range forces was responsible for binding under acidic conditions, whereas under alkaline conditions, a 1:1 Type A complex was the dominant species (Fitts et al, 1999). A comparison of the calculated Mn(II) dissolution rates also shows that Cu-Citrate 1:1 (oxic) falls between citric acid and ionic Cu(II).…”

Mineral Surfaces, Geochemical Complexities, and the Origins of Life

“…Dozens of recent studies reveal complexity in structure and speciation of adsorbed organics, particularly through in situ FTIR and other spectroscopic studies (Somasundaran and Krishnakumar 1994;Rodriguez et al 1996;Holmen et al 1997;Roddick-Lanzilotta et al 1998;Fitts et al 1999;Klug and Forsling 1999;Kubicki et al 1999;McQuillan 1999, 2000;Duckworth and Martin 2001;Sheals et al 2002;Lackovic et al 2003;Rosenqvist et al 2003;Yoon et al 2004Yoon et al , 2005Johnson et al 2004aJohnson et al , 2004bJohnson et al , 2004cJohnson et al , 2005aJohnson et al , 2005b (Thomas et al 1993;Orme et al 2001;Asthagiri and Hazen 2007). In addition, for the calcite-water interface, many theoretical simulations and observations exist to guide surface chemical models (Stipp and Hochella 1991;Parker 1997, 1999;Teng et al 1998Teng et al , 2000Fenter et al 2000;Wright et al 2001;Stipp 2002;de Leeuw and Cooper 2004;Geissbuhler et al 2004;Kristensen et al 2004).…”

“…Many investigations document significant variations in proportions of inner-to outer-sphere species as a function of pH or surface coverage (e.g., Hug and Sulzberger 1994;Fitts et al 1999;Nowack and Stone 1999;Roddick-Lanzilotta and McQuillan 2000;Lackovic et al 2003;Sheals et al 2003;Persson and Axe 2005). Proton titrations of oxide surfaces in electrolyte solutions, both with and without an organic adsorbate, provide powerful constraints on the possible reactions responsible for adsorption, particularly when used in combination with in situ attenuated total reflection Fourier transform infrared (ATR-FTIR) studies (Holman and Casey 1996;Nordin et al 1997;Boily et al 2000aBoily et al , 2000bBoily et al , 2000cBoily et al , 2005Sheals et al 2002Sheals et al , 2003Lackovic et al 2003;Lindegren et al 2005).…”

Mineral-Aqueous Solution Interfaces and Their Impact on the Environment

“…Additional methods, such as transmission electron microscopy, are often essential for characterising nano-scale precipitates containing the sorbing ion (e.g ., Towle et al ., 1997;Morin et al ., 2009) . In the case of cation sorption to particle surfaces in the presence of aqueous anions or organic molecules, Fourier transform infrared spectroscopy is very useful for assessing the presence or absence of ternary surface complexes involving aqueous metal cations and anions (or organic molecules) and mineral surface sites (e.g ., Bargar et al ., 1999;Fitts et al ., 1999;Ostergren et al ., 2000a,b;Ha et al ., 2008) .…”

“…As introduced in Section 7, Tom Trainor had already begun working on the application of LP-XSW-FY spectroscopy to the distribution of ions at mineral-water interfaces, so the stage was set for extending our studies of the interactions of aqueous ions with mineral surfaces to a more complex system in which a microbial biofilm coated the mineral surface . The questions we wished to address were how such a biofilm coating affected the reactivity of the underlying mineral surface and how the many carboxyl, phosphoryl, and phenolic and alcoholic hydroxyl functional groups in the biofilm coating competed for cations such as Pb (Bargar et al ., 1996(Bargar et al ., , 1997cFitts et al, 1999;Grolimund et al ., 1999;Trainor et al ., 2002b) . Our first biofilm study examined the partitioning of Pb When the maximum of the X-ray fluorescence yield (FY) occurs at the critical angle of the mineral substrate (~0 .…”