Dynamic studies with ARL EQUINOX 100 and BTS500 chamber

Importance of the topic

Accurate characterization of structural phase transitions under varying temperature conditions is critical for predicting material behavior in industrial, research, and quality-control settings. Real-time monitoring of these transformations enables rapid screening of new compounds and optimization of processing parameters, reducing time and resource investment.

Objectives and overview of the study

This application note demonstrates the capability of the Thermo Scientific ARL EQUINOX 100 combined with the Anton Paar BTS500 high-temperature chamber to perform dynamic X-ray diffraction (XRD) measurements on rubidium nitrate (RbNO3). The goal was to capture multiple phase transitions between room temperature and 350 °C within a single continuous experiment of less than three hours.

Methodology

Fine RbNO3 powder (99 % purity) was loaded into a nickel sample cup and heated from room temperature to 350 °C at a constant rate of 2 °C/min. Using Symphonix software, the XRD system was programmed for successive 2-minute acquisitions, generating a new full-pattern dataset every ~4 °C without holding at intermediate temperatures.

Instrumentation

• Thermo Scientific ARL EQUINOX 100 bench-top XRD with curved position sensitive detector (CPS).
• Anton Paar BTS500 compact high-temperature chamber (≤ 250 W power consumption).
• Copper micro-focus X-ray source (36 W, 40 kV, 0.9 mA) with SmartOptics beam conditioning.
• Symphonix control and data-acquisition software.

Main results and discussion

Over the temperature range studied, RbNO3 exhibited four distinct crystal structures:

• Trigonal phase from room temperature to ~160 °C.
• Rapid transition to a cubic form around 160–170 °C.
• Maintenance of the cubic phase up to ~250 °C.
• Transition to a rhombohedral phase at ~250–260 °C prior to melting.

These transitions were resolved through successive full-pattern measurements, demonstrating the system’s ability to capture transient structural changes without dwell periods.

Benefits and practical applications of the method

The described setup offers:

• High-throughput screening of phase behavior in under three hours.
• Minimal infrastructure requirements due to low power consumption and compact footprint.
• Real-time full-pattern acquisition enabling detection of rapid or overlapping transitions.

Future trends and applications

Further improvements may include targeted slow ramps around known transition points to refine transition temperatures and kinetics. Integration with automated sample stages and complementary in situ probes (e.g., thermal analysis or spectroscopy) will expand capabilities for multi-modal studies in materials science, ceramics, and battery research.

Conclusion

The ARL EQUINOX 100 with the BTS500 chamber delivers a cost-effective, rapid, and reliable platform for dynamic high-temperature XRD. This configuration successfully identified four RbNO3 polymorphs in a single continuous run, highlighting its potential for routine and research applications in phase-transition analysis.

References

No specific literature references were cited in the original document.