| Publication Type |
Journal Article |
| Title |
Size Matters: An Experimental and Computational Study of the Influence of Particle Size on the Lattice Energy of NaCl |
| Authors |
Sven Range Carlos E. S. Bernardes R. A. G. Simões Matthias Epple M. E. M. Piedade |
| Groups |
MET |
| Journal |
JOURNAL OF PHYSICAL CHEMISTRY C |
| Year |
2015 |
| Month |
February |
| Volume |
119 |
| Number |
8 |
| Pages |
4387-4396 |
| Abstract |
One of the most interesting features of nanomaterials is the change in properties that normally accompanies a decrease in particle size. Enthalpy of solution measurements in water, at 298 K, carried out with sodium chloride samples spanning a 500-fold particle size range (120 nm to 60 mu m) evidenced the effect of the increase in surface area to volume ratio in the enthalpy of solution and cohesive energy of NaCl. The nanoscopic samples were prepared by a new malonic ester synthesis, which allowed the production of well-formed and approximately cubic crystals. It was found that a very small change in lattice energy (similar to 0.01\%) can be translated into a comparatively much larger change in enthalpy of solution (similar to 4\%) and that the largest changes in properties are expected to occur for particle sizes below similar to 100 nm where a steep decrease in lattice energy (spanning a similar to 230 kJ.mol(-1) range) down to the limit of monomeric NaCl is expected to occur. The experimental findings were corroborated by the results of atom-atom pair potential calculations, which further suggested that the lattice energy within each crystal layer varies from site to site, with the energy differences between adjacent sites decreasing on moving from the periphery to the center of the crystal. The atoms at the outmost surface layer exhibit the lowest lattice energies. Finally the most stable atoms in terms of lattice energy are located in the second layer possibly because repulsive interactions with ions of similar type beyond the crystal surface are absent. |
| DOI |
http://dx.doi.org/10.1021/jp5124772 |
| ISBN |
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| Publisher |
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| Book Title |
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| ISSN |
1932-7447 |
| EISSN |
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| Conference Name |
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| Bibtex ID |
ISI:000350329300055 |
| Observations |
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