CRYSTAL GROWTH AND MAGNETISM OF THE ORGANIC LAYERED ANTIFERROMAGNET, DEUTERATED ?-(BEDT-TTF)2Cu[N(CN)2]Br; PENUMBUHAN KRISTAL DAN KEMAGNETAN DARI ANTIFERROMAGNET BERLAYER YANG ORGANIK, DEUTERATED ?-(BEDT-TTF)2Cu[N(CN)2]Br

ANGEL, JULIA, Kuwat Triyana

2016 | Disertasi | FMIPA

The large and high-quality crystals of the layered antiferromagnet deuterated ?-(BEDT-TTF)2Cu[N(CN)2]Br have been synthesized successfully by means of an electrochemical method controlling the applied current. Comparing to the previously reported studies, the largest single crystals are obtained from this research. Those single crystals are 9.45 mg, 15.13 mg, and 18.59 mg in weight. Even the crystal of 18.59 mg is almost two times larger than the largest crystal reported so far. The lightest one of those single crystals is used for the magnetization measurement conducted by the Superconducting Quantum Interference Device (SQUID) magnetometer. This material is characterized by M-H measurements for the first time. The small hysteresis behavior in the magnetization is found at 4.5 K around 500 G when the external field was applied in parallel and perpendicular to the conducting layers of deuterated ?-(BEDT-TTF)2Cu[N(CN)2]Br. The volume fraction of the superconductivity was evaluated in Meissner state to be (8.9 ± 0.2) % of the total volume. The enhancement of the magnetic transition temperature by the magnetic field, which is parallel to the conducting layers of deuterated ?-(BEDT-TTF)2Cu[N(CN)2]Br, is also found. The magnetic transition temperature increases slightly as the applied magnetic field increases.

Kata Kunci : deuterated ?-(BEDT-TTF)2Cu[N(CN)2]Br, electrochemical method with controlled applied current, crystal growth, largest single crystals, SQUID