Dy-SMM for Standalone Magneto Thermometry and Opto-Magnetic Temperature Sensing via Multiple Linear Regression

Area of Science:

• Materials Science
• Magnetism
• Nanotechnology

Background:

• Single-molecule magnets (SMMs) face challenges in thermal sensitivity due to a trade-off between magnetic and luminescent properties.
• Conventional thermometry strategies struggle to balance high symmetry for magnetic performance and low symmetry for luminescence efficiency.
• Enhancing SMM thermal sensitivity without synthetic modification or altering magnetic properties is a long-standing challenge.

Purpose of the Study:

• To develop a standalone magneto-thermometry tool for SMMs based on magnetic relaxation time and inverse magnetic susceptibility.
• To overcome low luminescence thermometry sensitivity in SMMs by integrating optical and magnetic sensing.
• To establish a multiparametric sensing strategy for precise, wide-range temperature sensing in SMMs.

Main Methods:

• Magneto-thermometry utilizing magnetic relaxation time (τ) and inverse magnetic susceptibility (1/χ).
• Application of multiple linear regression (MLR) to combine optical and magnetic parameters for multiparametric sensing.
• Characterization of an anilato-bridged dinuclear Dy-SMM for thermometric performance evaluation.

Main Results:

• Record high standalone relative magnetothermal sensitivities (Smax) of 11.91% K⁻¹ (Sr^τ) and 9.90% K⁻¹ (Sr^1/χ) achieved.
• S_r > 1% K^-1 observed across a wide temperature range (2-100 K), including the critical 2-45 K SMM operating range.
• Multiparametric opto-magnetic thermometry using MLR achieved S_max = 69.58% K^-1 (at 15 K) with S_r > 40% K^-1 in the SMM regime.

Conclusions:

• Magneto-thermometry is a powerful standalone tool for SMM temperature sensing.
• MLR-based opto-magnetic thermometry offers a significant advancement for precise, wide-range temperature sensing in SMMs.
• This strategy effectively overcomes the limitations of conventional thermometric approaches in SMM systems.