MD simulations using accurate force fields allow studying biomembranes at different conditions to interpret experimental results and to get knowledge of membrane structure and the function, and dynamics of membrane-bound proteins. Here we demonstrate the performance of OPLS3e to be reasonably accurate for POPC membranes at full hydration and upon dehydration: The C-H bond order parameters produced with OPLS3e behave similarly to the well-established membrane force field CHARMM36 and closely follow the experimental observations. However, extreme caution should be exercised with systems containing ions, especially Ca 2+ ions: OPLS3e, similarly to most other force fields, overestimates the binding of the cationic ions to the membrane which both disrupts the neutral net charge of the membrane surface and changes the concentration of ions in the surrounding solvent. These issues could affect, for example, the structure and dynamics of the charged domains of membrane-bound proteins in unexpected ways.