Table 1.
Distances between atoms (Å), bonds angles (°) and geometric aromaticity indices calculated for trans o-coumaric acid and lithium, sodium and potassium o-coumarates.
| Acid | Li | Na | K | ||
|---|---|---|---|---|---|
| Calculated | Experimental [22] | Calculated | |||
| Distances [Å] | |||||
| C1-C2 a | 1.412 | 1.401 | 1.411 | 1.412 | 1.411 |
| C2-C3 | 1.396 | 1.389 | 1.396 | 1.397 | 1.396 |
| C3-C4 | 1.389 | 1.368 | 1.390 | 1.391 | 1.391 |
| C4-C5 | 1.396 | 1.379 | 1.396 | 1.397 | 1.395 |
| C5-C6 | 1.387 | 1.379 | 1.388 | 1.389 | 1.389 |
| C6-C1 | 1.406 | 1.394 | 1.405 | 1.407 | 1.405 |
| C1-C9 | 1.460 | 1.466 | 1.464 | 1.466 | 1.466 |
| C7-C8 | 1.471 | 1.460 | 1.481 | 1.343 | 1.497 |
| C8-C9 | 1.344 | 1.337 | 1.343 | 1.501 | 1.341 |
| C2-O3 | 1.365 | 1.353 | 1.368 | 1.369 | 1.370 |
| C7-O1 | 1.364 | 1.329 | 1.278 | 1.270 | 1.272 |
| C7-O2 | 1.211 | 1.229 | 1.276 | 1.266 | 1.268 |
| O3-H2 | 0.963 | 0.790 | 0.963 | 0.965 | 0.962 |
| C3-H3 | 1.086 | 0.904 | 1.086 | 1.086 | 1.087 |
| C4-H4 | 1.084 | 0.989 | 1.084 | 1.084 | 1.084 |
| C5-H5 | 1.083 | 0.917 | 1.083 | 1.083 | 1.084 |
| C6-H6 | 1.083 | 1.082 | 1.083 | 1.083 | 1.083 |
| C8-H7 | 1.083 | 1.059 | 1.084 | 1.085 | 1.085 |
| C9-H8 | 1.085 | 0.613 | 1.084 | 1.084 | 1.084 |
| O1-H1(M) | 0.968 | 0.987 | 1.854 | 2.372 | 2.516 |
| O2-Me | - | - | 1.850 | 2.365 | 2.509 |
| Angles [°] | |||||
| C1-C2-C3 | 120.867 | 120.590 | 121.014 | 121.063 | 121.145 |
| C2-C3-C4 | 120.181 | 119.880 | 120.253 | 120.152 | 120.338 |
| C3-C4-C5 | 120.066 | 120.410 | 119.881 | 119.962 | 119.699 |
| C4-C5-C6 | 119.522 | 120.310 | 119.565 | 119.578 | 119.609 |
| C5-C6-C1 | 121.962 | 120.590 | 122.110 | 122.015 | 122.262 |
| C6-C1-C2 | 117.402 | 118.210 | 117.177 | 117.230 | 116.947 |
| C2-C1-C9 | 119.370 | 118.660 | 119.606 | 119.585 | 119.781 |
| C1-C9-C8 | 126.973 | 126.160 | 126.882 | 127.421 | 126.824 |
| C7-C8-C9 | 120.355 | 120.130 | 121.977 | 122.953 | 122.615 |
| C8-C7-O1 | 111.123 | 112.460 | 118.273 | 116.528 | 116.496 |
| C8-C7-O2 | 126.998 | 126.060 | 121.069 | 119.740 | 119.511 |
| C7-C8-H7 | 116.222 | 116.610 | 114.692 | 114.930 | 114.494 |
| C9-C8-H7 | 123.423 | 123.250 | 123.332 | 122.117 | 122.891 |
| C8-C9-H8 | 116.851 | 117.230 | 116.776 | 116.648 | 116.691 |
| C1-C9-H8 | 116.176 | 86.400 | 116.342 | 115.931 | 116.486 |
| C9-C1-C2 | 119.370 | 118.660 | 119.606 | 119.585 | 119.781 |
| C1-C2-O3 | 119.370 | 116.780 | 117.705 | 117.807 | 117.759 |
| C3-C2-O3 | 119.370 | 122.620 | 121.281 | 121.130 | 121.096 |
| C3-C4-H4 | 119.370 | 118.660 | 119.661 | 119.595 | 119.736 |
| C4-C5-H5 | 119.370 | 125.840 | 120.326 | 120.338 | 120.331 |
| C6-C5-H5 | 119.370 | 113.680 | 120.109 | 120.085 | 120.060 |
| C5-C6-H6 | 119.370 | 118.640 | 119.100 | 119.048 | 119.119 |
| C1-C6-H6 | 119.370 | 120.600 | 118.790 | 118.937 | 118.619 |
| C6-C1-C9 | 119.370 | 123.130 | 123.217 | 123.185 | 123.272 |
| C9-C8-C7 | 120.355 | 120.130 | 121.977 | 122.953 | 122.615 |
| C5-C4-H4 | 120.344 | 120.930 | 120.458 | 120.443 | 120.566 |
| C2-O3-H2 | 110.021 | 114.110 | 109.702 | 109.812 | 109.442 |
| C7-O1-H1(M) | 106.701 | 110.930 | 82.753 | 89.771 | 91.302 |
| O1-C7-O2 | 121.879 | 121.480 | 120.657 | 123.732 | 123.994 |
| C7-O2-M | - | - | 82.988 | 90.165 | 91.693 |
| O1-M-O2 | - | - | 73.601 | 56.332 | 53.011 |
| C1-C9-C8-C7 | −179.998 | −179.210 | 179.998 | −179.999 | 179.998 |
| C6-C1-C9-C8 | 0.011 | 7.290 | −0.023 | −0.030 | −0.023 |
| C9-C8-C7-O1 | −179.999 | 176.670 | 179.999 | 179.994 | 179.999 |
| C9-C8-C7-O2 | 0.002 | −2.790 | 0.004 | −0.004 | 0.004 |
a: Atom numbering.