Interaction of ethanol and water with the {1014} surface of calcite

TY - JOUR

T1 - Interaction of ethanol and water with the {1014} surface of calcite

AU - Cooke, David

AU - Gray, R J

AU - Sand, K K

AU - Stipp, S L S

AU - Elliott, J A

PY - 2010/9/21

Y1 - 2010/9/21

N2 - Molecular dynamics simulations have been used to model the interaction between ethanol, water, and the {1014} surface of calcite. Our results demonstrate that a single ethanol molecule is able to form two interactions with the mineral surface (both Ca-O and O-H), resulting in a highly ordered, stable adsorption layer. In contrast, a single water molecule can only form one or other of these interactions and is thus less well bound, resulting in a more unstable adsorption layer. Consequently, when competitive adsorption is considered, ethanol dominates the adsorption layer that forms even when the starting configuration consists of a complete monolayer of water at the surface. The computational results are in good agreement with the results from atomic force microscopy experiments where it is observed that a layer of ethanol remains attached to the calcite surface, decreasing its ability to interact with water and for growth at the {1014} surface to occur. This observation, and its corresponding molecular explanation, may give some insight into the ability to control crystal form using mixtures of different organic solvents.

AB - Molecular dynamics simulations have been used to model the interaction between ethanol, water, and the {1014} surface of calcite. Our results demonstrate that a single ethanol molecule is able to form two interactions with the mineral surface (both Ca-O and O-H), resulting in a highly ordered, stable adsorption layer. In contrast, a single water molecule can only form one or other of these interactions and is thus less well bound, resulting in a more unstable adsorption layer. Consequently, when competitive adsorption is considered, ethanol dominates the adsorption layer that forms even when the starting configuration consists of a complete monolayer of water at the surface. The computational results are in good agreement with the results from atomic force microscopy experiments where it is observed that a layer of ethanol remains attached to the calcite surface, decreasing its ability to interact with water and for growth at the {1014} surface to occur. This observation, and its corresponding molecular explanation, may give some insight into the ability to control crystal form using mixtures of different organic solvents.

KW - Calcium Carbonate

KW - Ethanol

KW - Microscopy, Atomic Force

KW - Models, Molecular

KW - Molecular Conformation

KW - Reproducibility of Results

KW - Surface Properties

KW - Water

U2 - 10.1021/la100670k

DO - 10.1021/la100670k

M3 - Journal article

C2 - 20795691

SN - 0743-7463

VL - 26

SP - 14520

EP - 14529

JO - Langmuir

JF - Langmuir

IS - 18

ER -