Subcategory: Materials Science
Gabriel Lopez - California State University, San Bernardino
Co-Author(s): Kevin Collins, California State University, San Bernardino, CA.
We have synthesized a completely new crystalline material that has exhibited two distinct morphologies with the possibility of being ferroelectric. This crystal is theorized to be ferroelectric, meaning it can remember electric fields, and can be used as capacitors, actuators, data memory storages, and many other important applications. We mix equal parts of: a one mole standard solution Cobalt (II) Chloride Hexahydrate (237.93g/L), Hydrochloric Acid (HCL), and Diisopropylamine (DIPA). Fast evaporation of the solution results in a needle like morphology, while slow evaporation results in a plate morphology. Powder x-ray diffraction shows that needles and plates have the same pattern or same structure. The new crystal, Diisopropylammonium Cobalt (II), was characterized by single crystal x-ray diffraction; the structure consists of 8[CoCl4] 2[HDIPA] units per unit cell and has the molecular formula Cl4 Co, 2(C6 H16 N). The crystal symmetry group is C 1 2 1, its unit cell dimensions are a = 28.3559(12) Å α= 90°. b = 12.1289(6) Å β= 118.2520(10) °. c = 13.5484(5) Å = 90°. VASP calculation shows the polarization to be -33 electrons-Angstrom along the y-axis, which is 28 degrees off the b-axis. These results suggest that this crystal may be ferroelectric with high probability to pass through polar phases due to its spacing. Further testing with Atomic Force Microscopy and Radiance Systems are needed to confirm ferroelectric and piezoelectric properties.
Funder Acknowledgement(s): NSF CREST Grant #1345163
Faculty Advisor: Timothy Usher, firstname.lastname@example.org
Role: I synthesized the new organic material using the components Cobalt (II) Chloride Hexahydrate, Hydrochloric Acid (HCl), and Diisopropylamine (DIPA). I monitored evaporation rates and extracted crystals, cleaned, and prepared crystal samples. I used a Philips X'Pert X-ray Diffractometer to characterize crystals making sure my crystal production was consistent and to confirm that the two morphologies of the crystal were the same structurally.