This paper aims to explore the influence of solvent effects on the crystal habit of venlafaxine hydrochloride using the modified attachment energy (MAE) model by molecular dynamics (MD) simulation. Solvent effects were investigated based on the different morphologies of venlafaxine hydrochloride acquired by simulation and experimental technology from the solvents of isopropanol, dimethyl sulfoxide, and acetonitrile. Firstly, morphologically dominant crystal faces were obtained through the prediction of crystal habit in vacuum by the attachment energy (AE) model. Subsequently, the MAEs were calculated by the MD simulation to modify the crystal shapes in a real solvent environment, and the simulation results were in agreement with the experimental ones. Meanwhile, in order to have a better understanding of the solvent effects, the surface structure was introduced to analyze the solvent adsorption behaviors. The results show that the crystal habits of venlafaxine hydrochloride are affected by the combination of the AE and surface structures. Finally, the flowability of the obtained crystal powders from different solvents was investigated by measurement and analysis of the angle of repose and compressibility. The above results verify that the physical properties are closely related to the morphologies of the crystals.

Living systems exert exquisite control on all aspects of biomineral production and organic components, including proteins, are essential to this biological control. The protein-rich extrapallial (EP) fluid of bivalve molluscs is a strong candidate for the source of such proteins. Differences in calcium carbonate polymorphs between Modiolus modiolus and Mytilus edulis are concurrent with differences in EP fluid protein profiles. In conjunction with this biological control is the environmental influence which is interpreted using proxies such as δ18O to determine the history of ambient seawater temperature. In the horse mussel, Modiolus modiolus, the difference in oxygen isotope fractionation in the nacreous aragonite and the prismatic aragonite layer results in respective δ18O values of 2.1±0.2% and 2.5±0.2%. These δ18O values result in estimates of ambient seawater of 12.1±0.6°C and 10.2±0.6°C for nacreous and prismatic aragonite, respectively. Electron backscatter diffraction is used here to determine the crystallographic orientation at high spatial resolution, allowing the measurements of stable isotopes to be accurately mapped in terms of shell architecture. These preliminary data suggest that it is essential to account for both polymorph and crystal habit when deciphering ambient seawater temperature using δ18O as a proxy.