TY - JOUR
T1 - Quantum chemical adsorption studies on the (110) surface of the mineral goethite
AU - Aquino, Adelia J.A.
AU - Tunega, Daniel
AU - Haberhauer, Georg
AU - Gerzabek, Martin H.
AU - Lischka, Hans
PY - 2007/1/18
Y1 - 2007/1/18
N2 - The interaction between the (110) goethite surface and water, acetic acid, acetate, 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4-dichlorophenoxyacetate (2,4-D-), and benzene was studied by means of quantum mechanical calculations based on density functional theory (DFT) using the B3LYP approach. Furthermore, Møller -Plesset calculations to second order using the resolution-of-identity approach (RI-MP2) were also performed for the goethite/benzene interaction. Structural and energetic features of the surface complexes were evaluated using cluster models for the goethite surface derived from a periodic slab surface. Our investigations showed that the (110) goethite surface formed by three types of the hydroxyl groups offers a variety of possibilities for hydrogen bond formation with appropriate polar adsorbents. Calculated interaction energies for the water molecule on different sites are on the order of ca. -20 kcal/mol, a number that is in line with the number and type of hydrogen bonds formed. Comparison of the interaction energies for different interaction sites/clusters shows that these sites are energetically more or less equivalent. Slightly larger interaction energies were observed for acetic acid and 2,4-D in comparison with the goethite/water complexes. The deprotonated, anionic form of acetic acid and 2,4-D show even stronger interactions between -30 and -50 kcal/mol. The interaction with the nonpolar, aromatic benzene molecule is significantly weaker (estimated value is in the range of -5 to -9 kcal/mol) but still significant.
AB - The interaction between the (110) goethite surface and water, acetic acid, acetate, 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4-dichlorophenoxyacetate (2,4-D-), and benzene was studied by means of quantum mechanical calculations based on density functional theory (DFT) using the B3LYP approach. Furthermore, Møller -Plesset calculations to second order using the resolution-of-identity approach (RI-MP2) were also performed for the goethite/benzene interaction. Structural and energetic features of the surface complexes were evaluated using cluster models for the goethite surface derived from a periodic slab surface. Our investigations showed that the (110) goethite surface formed by three types of the hydroxyl groups offers a variety of possibilities for hydrogen bond formation with appropriate polar adsorbents. Calculated interaction energies for the water molecule on different sites are on the order of ca. -20 kcal/mol, a number that is in line with the number and type of hydrogen bonds formed. Comparison of the interaction energies for different interaction sites/clusters shows that these sites are energetically more or less equivalent. Slightly larger interaction energies were observed for acetic acid and 2,4-D in comparison with the goethite/water complexes. The deprotonated, anionic form of acetic acid and 2,4-D show even stronger interactions between -30 and -50 kcal/mol. The interaction with the nonpolar, aromatic benzene molecule is significantly weaker (estimated value is in the range of -5 to -9 kcal/mol) but still significant.
UR - http://www.scopus.com/inward/record.url?scp=33847633484&partnerID=8YFLogxK
U2 - 10.1021/jp0649192
DO - 10.1021/jp0649192
M3 - Article
AN - SCOPUS:33847633484
VL - 111
SP - 877
EP - 885
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 2
ER -