Nuclear Magnetic Resonance & Magnetic Testing Facility

The NMR facility provides a sophisticated approach for the investigations of macromolecules in solution and in solid state. The current NMR research work falls into two general areas: i) Solid state NMR study of structure and morphology of polymers, miscibility of polymer blends, and interface behavior of polymer composites, as well as the degradation of biopolymers; ii) Multidimensional and multinuclear NMR investigations of membrane or receptor bound biological molecules to obtain information on their structure/conformational requirements at their receptor sites of action.

Bruker DMX500 high resolution digital NMR spectrometer

is a state-of-the-art 500MHz system with four-channel operation and pulsed field gradients. The spectrometer is equipped with a 5 mm inverse triple resonance gradient probe with a three-axes XYZ Acustar II gradient accessory, a 5 mm multinuclear broadband probe, and a BVT-2000 Eurotherm digital VT control unit. The system is coupled with a high speed SGI INDY workstation computer with 12 GB disk space, operating Bruker XWINNMR software allowing for a wide variety of 1-D, 2-D and 3-D NMR experiments.

Otsuka Chemagnetics CMX-II 300 & Bruker DMX/DSX 300

are 300 MHz solid state triple resonance spectrometers. The systems are equipped with an 89 mm Oxford magnet and is a dedicated NMR spectrometer for solids, and provides capabilities for magic-angle spinning, static high-power experiments and multi-pulse experiments. They are furnished with a temperature control unit, a MAS spin speed controller, two multinuclear double resonance magic angle spinning (MAS) probes (5 and 7.5 mm), a 5 mm multinuclear triple resonance MAS probe, and a stationary 2H probe.

Computer modeling is also integrated into this research effort utilizing a SGI Octane R10000 computer running Tripos SYBYL software (v. 6.5) and a Power Indigo2 EXTREME SGI computer with Biosym InsightII/Discover software.

Nuclear Magnetic Resonance

a new laboratory-built pulsed NMR spectrometer suitable for solids which is capable of operation from 3 to 1000 MHz with an output power ranging from 100 to 200 Watts depending on the frequency. The system features two receiving channels along with four-quadrant phase-coherent detection and phase cycling. Two Matec NMR spectrometer are also available: a model 5100 phase coherent gated amplifier which operates from 0.50 to 150 MHz with an RF output power up to 1.0 kWatt and a model 7700 non-coherent pulsed oscillator which operates from 10 to 700 MHz with an RF output power up to 1 kWatt. A liquid helium cryostat enables operation down to 1.3 K.

Bulk Magnetization

A Princeton Applied Research Corporation model 155 vibrating sample magnetometer is available which permits continuous operation between 2.5 and 1270 K and for magnetic fields up to 20 kOe. This versatile instrument enables magnetization measurements to be made on a wide variety of materials with a sensitivity of a 1.0 x 10-4emu. A Quantum Design model MPMS SQUID magnetometer is available which permits continuous operation between 2.0 and 400K, and for magnetic fields up to 55 kOe. This highly automated and sensitive instrument enables magnetization measurements to be made on samples which magnetic moments as small as 1.0 x 10-5emu.

Impedance Analyzer

The Hewlett Packard model 4192A low frequency (5 Hz to 13MHz) impedance analyzer is a fully automatic, high performance test instrument designed to measure a wide range of impedance parameters as well as gain, phase and group delay. This instrument is utilized to measure the real and imaginary parts of the magnetic susceptibility for new nano-scale magnetic materials.

Radiant Technologies Work Station

This equipment is utilized to measure the ferroelectric and dielectric properties of materials. Together with a precise probing unit, it is possible to conduct measurements on thin films and bulk materials that are Page 6coated/supplied with electrodes. The hysteresis response of the sample under various signals can be precisely determined from which ferroelectric and dielectric properties are derived. A heating-cooling stage is present to make measurements at a temperature ranging from 100°C to 500°C to determine the temperature dependency of the electrical properties.

Pulsed Laser Deposition Unit

Pulsed Laser Deposition (PLD) method is a thin film deposition method widely used today to grow high-quality thin films in this case ferroelectric perovskite thin films on various substrates.