Guest-dependent T 2 of DAT triplets in D-MIL-53. a, Spin echo sequence used for T2 measurement. The intervals of microwave pulses and echo detection were varied. b, Plot of T2 obtained by the single-exponential fitting of the spin echo decay curves against the unit cell volume of MIL-53. Only the T2 obtained from the low field peaks where the effect of ESEEM was small is plotted. c, Spin echo decay curves after pulsed photoexcitation at 532 nm for empty (D-MIL-53⸧DAT) and guest-filled (D-MIL-53⸧[DAT+guest]) samples at room temperature. The decay curves of each sample at the magnetic field corresponding to the higher and lower EPR peaks (Fig. 3a) are shown at the top and bottom, respectively. Single-exponential fitting curves for each sample are also shown. Echo signals were not observed when the guest was h-Tol, EtOH, or AcNt.

Contexts in source publication

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... coherence time (T 2 ). The coherence times (T2) of the photoexcited triplets of DAT in D-MIL-53 were measured by pulsed EPR at room temperature with a spin echo sequence varying the pulse intervals ( Fig. 2a). Measurements were taken at the magnetic field of the high-field and low-field peaks of the EPR spectra shown later, respectively, and both decay curves are shown (Fig. 2c). The decay of echo intensity was fitted with a single exponential function and T2 was obtained as the decay constant. While DAT shows electron spin echo envelope ...

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... The coherence times (T2) of the photoexcited triplets of DAT in D-MIL-53 were measured by pulsed EPR at room temperature with a spin echo sequence varying the pulse intervals ( Fig. 2a). Measurements were taken at the magnetic field of the high-field and low-field peaks of the EPR spectra shown later, respectively, and both decay curves are shown (Fig. 2c). The decay of echo intensity was fitted with a single exponential function and T2 was obtained as the decay constant. While DAT shows electron spin echo envelope modulation (ESEEM) due to hyperfine coupling with 1 H nuclei and 14 N nuclei at higher magnetic field, it does not affect the estimation of T2. The T2 values obtained at the ...

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... T2 value was plotted against the cell volume of MIL-53 ( Fig. 2b). With increasing cell volume, T2 shows a non-monotonic trend, becoming longer and then shorter. Triplet qubit and flexible MOF hybrids exhibit different coherence times for various guest molecules, enabling room-temperature quantum chemical sensing of neutral molecules that has not been reported previously. b, Plot of T2 obtained by ...

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... immediately absorbs water and forms a hydrated structure), DAT shows absorption peaks at 450, 480, and 515 nm derived from π-π* transitions. This is consistent with the absorption peaks of DAT molecularly dispersed in p-terphenyl and is clearly different from the red-shifted peaks of DAT in its aggregated solid state, as we previously reported 32 (Fig. S2). With the exception of BQ, where the guest itself shows absorption, no significant change in the absorption spectrum is observed when various guest molecules are introduced (Fig. S3). This indicates that the interaction between DAT and the guest molecules is small in the ground state and that DAT is not aggregated by the introduction ...