Table 1.
B3LYP/6-311 + G(d,p) optimized relevant bond lengths (Å), bond angles (deg) and dihedral angles (deg) for the metal-coordinated and hydrated complexes of L-phenylalanine, L-tryptophan, and L-tyrosine species
| Parameters | (Phe···M2+) x (H2O)n | (Trp···M2+) x (H2O)n | (Tyr···M2+) x (H2O)n | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ni2+ | Cu2+ | Zn2+ | Ni2+ | Cu2+ | Zn2+ | Ni2+ | Cu2+ | Zn2+ | ||||||||||
| n = 0 | n = 5 | n = 0 | n = 5 | n = 0 | n = 5 | n = 0 | n = 6 | n = 0 | n = 6 | n = 0 | n = 6 | n = 0 | n = 6 | n = 0 | n = 6 | n = 0 | n = 6 | |
| d[C(1)–C(2)] | 1.536 | 1.526 | 1.547 | 1.516 | 1.524 | 1.530 | 1.534 | 1.516 | 1.544 | 1.521 | 1.535 | 1.520 | 1.538 | 1.525 | 1.546 | 1.521 | 1.535 | 1.529 |
| d[C(2)–O(3)] | 1.233 | 1.250 | 1.219 | 1.253 | 1.253 | 1.247 | 1.224 | 1.251 | 1.220 | 1.241 | 1.233 | 1.249 | 1.227 | 1.251 | 1.219 | 1.243 | 1.239 | 1.247 |
| d[C(2)–O(4)] | 1.300 | 1.281 | 1.312 | 1.279 | 1.287 | 1.282 | 1.309 | 1.282 | 1.313 | 1.289 | 1.299 | 1.283 | 1.306 | 1.282 | 1.313 | 1.289 | 1.295 | 1.283 |
| d[C(1)–N(6)] | 1.500 | 1.496 | 1.485 | 1.501 | 1.512 | 1.494 | 1.494 | 1.501 | 1.488 | 1.491 | 1.486 | 1.495 | 1.495 | 1.496 | 1.487 | 1.495 | 1.491 | 1.495 |
| d[N(6)···M(5)] | 2.035 | 2.057 | 2.106 | 2.019 | 2.036 | 2.104 | 2.048 | 2.043 | 2.097 | 2.065 | 2.157 | 2.064 | 2.044 | 2.050 | 2.103 | 2.066 | 2.117 | 2.093 |
| d[O(3)···M(5)] | 1.965 | 2.008 | 2.082 | 1.961 | 1.963 | 2.080 | 1.990 | 1.972 | 2.087 | 2.017 | 2.067 | 2.011 | 1.982 | 2.013 | 2.090 | 2.011 | 2.027 | 2.087 |
| Θ[C(1)–C(2)–O(3)] | 122.0 | 119.3 | 122.9 | 120.9 | 123.3 | 119.5 | 123.1 | 121.2 | 123.5 | 121.2 | 122.9 | 121.8 | 122.3 | 119.2 | 123.3 | 121.5 | 122.8 | 119.5 |
| Θ[C(2)–C(1)–N(6)] | 108.1 | 107.1 | 109.0 | 108.1 | 110.0 | 107.3 | 108.7 | 108.6 | 109.4 | 108.1 | 108.6 | 109.5 | 108.3 | 107.0 | 109.3 | 108.7 | 108.5 | 107.3 |
| Θ[C(1)–N(6)···M(5)] | 108.2 | 105.7 | 109.3 | 111.5 | 109.7 | 106.0 | 108.8 | 110.3 | 109.4 | 110.1 | 109.9 | 108.9 | 108.4 | 105.6 | 109.4 | 110.9 | 109.5 | 106.0 |
| Θ[C(2)–O(3)···M(5)] | 113.7 | 113.8 | 113.4 | 115.7 | 110.8 | 113.8 | 113.2 | 115.2 | 112.7 | 115.1 | 115.2 | 113.6 | 113.6 | 113.5 | 113.0 | 115.3 | 114.6 | 113.3 |
| Θ[O(3)···M(5)···N(6)] | 84.8 | 81.8 | 81.6 | 83.5 | 87.7 | 79.7 | 84.6 | 83.6 | 82.1 | 81.8 | 80.0 | 83.8 | 84.3 | 81.9 | 81.8 | 82.4 | 81.8 | 79.8 |
| Φ[O(3)–C(2)–C(1)–N(6)] | 13.1 | 26.7 | 15.2 | -5.3 | -15.2 | 28.1 | -11.2 | -11.6 | 11.4 | -16.7 | 10.9 | -16.3 | 12.9 | 27.5 | 12.8 | -12.8 | 10.0 | 28.4 |
| Φ[C(2)–C(1)–N(6)···M(5)] | -17.8 | -35.8 | -20.3 | 1.8 | 16.1 | -38.0 | 13.3 | 8.9 | -17.2 | 20.2 | -18.2 | 15.8 | -17.9 | -36.6 | -18.4 | 10.4 | -16.6 | -38.7 |
| Φ[C(1)–C(2)–O(3)···M(5)] | -0.5 | -1.9 | -0.9 | 6.3 | 4.8 | -1.8 | 2.3 | 8.2 | 1.2 | 3.9 | 3.2 | 7.4 | -0.2 | -2.2 | 0.4 | 8.4 | 2.9 | -1.7 |