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Vapochromic behaviour of M[Au(CN)2]2-based coordination polymers (M = Co, Ni)
Julie Lefebvre1, Jasmine L Korčok, Michael J Katz
1Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada. jlefebvr@ucalgary.ca
Sensors (Basel, Switzerland)
|June 28, 2012
Summary
Cobalt coordination polymers exhibit visible vapochromism upon exposure to analyte vapors, unlike nickel analogs. These materials, including M[Au(CN)2]2(analyte)x, offer insights into coordination chemistry and material responses.
Area of Science:
- Coordination Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Coordination polymers based on M[Au(CN)2]2 frameworks are known for their diverse structural motifs.
- Vapochromism, a change in color upon exposure to vapor, is a desirable property for sensing applications.
Purpose of the Study:
- To synthesize and characterize a series of M[Au(CN)2]2(analyte)x coordination polymers (M = Co, Ni; analyte = DMSO, DMF, pyridine).
- To investigate the vapochromic properties of these coordination polymers.
- To elucidate the structural changes associated with analyte absorption.
Main Methods:
- Synthesis of coordination polymers via solution-phase reactions and vapor absorption.
- Characterization using single-crystal X-ray diffraction and infrared (IR) spectroscopy.
- Investigation of solid-state responses to analyte vapors.
Main Results:
- Cobalt-based coordination polymers (M = Co) displayed visible vapochromic responses to analyte vapors, while nickel analogs (M = Ni) did not.
- IR spectroscopy confirmed changes in the ν(CN) region for all complexes upon analyte interaction.
- Crystal structures revealed diverse frameworks, including 2-D corrugated layers and flat 2-D square-grids, with varying analyte coordination (cis or trans).
Conclusions:
- The study demonstrates that cobalt coordination polymers exhibit vapochromism, making them potential candidates for vapor sensing.
- Structural analysis provides a basis for understanding the mechanism of vapochromic response.
- The coordination polymers can be synthesized through different routes, including vapor absorption and solution-phase methods.
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