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Rigidochromism of tetranuclear Cu(I)–pyrazolate macrocycles: steric crowding with trifluoromethyl groups
Macrocyclic Cu(I)–pyrazolate tetramers (Cu4pz4) can fold into compact structures with luminescent Cu4 cores whose emission wavelengths are sensitive to steric effects along the periphery of the macrocycle. Introducing CF3 at the C4 position of 3,5-di-tBu-pyrazolate increases steric crowding that modifies the conformational behavior of the Cu4pz4 complex, highlighted by a low-temperature martensitic transition. Variable-temperature analysis of solid-state luminescence reveal an unexpected blueshifting of emission with rising temperature.
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- Award ID(s):
- 2204206
- PAR ID:
- 10612654
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemistry Communications
- ISSN:
- 1359-7345
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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