Table 1.
Resonator and sample cell characteristics calculated and measured. EPR signals are at constant microwave field and normalized to a 1 mm capillary in a cylindrical TE011, while Λave can be directly compared.
| Geometry | freq. [GHz] | Q-value | Norm. Signal | Λave [G/W1/2] | Vol. [μL] | ||||
|---|---|---|---|---|---|---|---|---|---|
| Meas. | Calc. | Meas. | Calc. | Meas. | Calc. | Meas. | Calc. | ||
|
| |||||||||
| Two-Loop–One-Gap | |||||||||
|
| |||||||||
| TPX (0.6 mm I.D.) | 9.23 | 9.34 | 204 | 268 | 0.21 | 0.32 | 5.61 | 4.37 | 2.2 |
| DoubleDee Par. | 9.31 | 9.41 | 419 | 408 | 0.31 | 0.43 | 6.83 | 5.32 | 3.2 |
| DoubleDee Perp. | 9.29 | 9.38 | 387 | 352 | 0.25 | 0.39 | 5.82 | 4.96 | 3.2 |
|
| |||||||||
| Five-Loop–Four-Gap | |||||||||
|
| |||||||||
| Capillary (1 mm I.D.) | 9.56 | 9.75 | 620 | 802 | 0.35 | 0.35 | 1.67 | 1.78 | 7 |
| AquaStar | 9.44 | 9.63 | 673 | 640 | 0.83 | 0.81 | 1.52 | 1.61 | 25 |
|
| |||||||||
| Cylindrical TE011 | |||||||||
|
| |||||||||
| Capillary (1 mm I.D.) | 9.86 | 9.58 | 3651 | 6640 | 1 | 1 | 1.12 | 1.45 | 30 |
| AquaX | 9.86 | 9.53 | 2466 | 4040 | 3.24 | 3.17 | 0.52 | 0.47 | 143 |
| AquaStar | 9.86 | 9.58 | 2530 | 5154 | 3.02 | 2.97 | 0.68 | 0.78 | 100 |
| AquaSun | – | 9.43 | – | 1848 | – | 8.18 | – | 0.52 | 396 |