Research Article
Experimental and Theoretical Investigations of Terahertz Spectra of the Structural Isomers: Mannose and Galactose
Table 2
Calculated bond angles (°) and RMSD values of mannose and galactose compared to experimental X-ray valuesa.
| Mannose | Galactose | CASTEP | Gaussian | CASTEP | Gaussian | Bond angle | Exp. | PBE | PW91 | B3LYP | Bond angle | Exp. | PBE | PW91 | B3LYP |
| O1–C1–O5 | 105.60 | 106.28 | 106.82 | 108.25 | O1–C2–O5 | 111.83 | 110.61 | 110.61 | 109.84 | O1–C1–C2 | 115.70 | 113.76 | 113.94 | 111.16 | O1–C2–C3 | 108.11 | 112.12 | 112.47 | 110.17 | O5–C1–C2 | 111.00 | 109.66 | 110.06 | 110.72 | C3–C2–O5 | 107.55 | 110.74 | 110.82 | 111.24 | O2–C2–C1 | 106.30 | 108.50 | 108.59 | 106.63 | C2–C3–C4 | 110.07 | 108.72 | 108.80 | 111.67 | O2–C2–C3 | 112.20 | 112.50 | 112.54 | 110.62 | C2–C3–O2 | 109.34 | 108.89 | 108.75 | 109.97 | C1–C2–C3 | 107.60 | 108.53 | 109.06 | 111.88 | O2–C3–C4 | 112.90 | 113.79 | 113.84 | 106.72 | O3–C3–C4 | 111.80 | 111.28 | 111.87 | 111.45 | C3–C4–C1 | 109.77 | 108.88 | 108.78 | 109.77 | O3–C3–C2 | 107.60 | 109.58 | 108.78 | 107.04 | C3–C4–O3 | 110.79 | 111.71 | 111.69 | 111.15 | C4–C3–C2 | 112.90 | 112.12 | 112.36 | 111.13 | O3–C4–C1 | 110.14 | 112.74 | 112.78 | 110.35 | O4–C4–C3 | 106.20 | 107.02 | 106.82 | 105.92 | C4–C1–C5 | 107.75 | 107.48 | 107.49 | 107.18 | O4–C4–C5 | 111.80 | 111.00 | 111.27 | 113.37 | C4–C1–O4 | 110.79 | 112.90 | 112.79 | 112.58 | C3–C4–C5 | 110.90 | 110.08 | 109.34 | 109.02 | O4–C1–C5 | 113.36 | 113.26 | 113.24 | 110.73 | O5–C5–C4 | 111.70 | 111.46 | 110.86 | 108.63 | C1–C5–O5 | 110.64 | 111.04 | 111.14 | 107.79 | O5–C5–C6 | 107.00 | 105.89 | 106.71 | 105.56 | C1–C5–C6 | 113.15 | 115.73 | 115.59 | 114.15 | C4–C5–C6 | 111.50 | 112.61 | 113.04 | 114.44 | O5–C5–C6 | 105.42 | 103.31 | 103.29 | 107.00 | O6–C6–C5 | 110.80 | 111.54 | 112.35 | 111.30 | C5–C6–O6 | 109.18 | 113.13 | 113.19 | 111.02 | C5–O5–C1 | 112.20 | 113.43 | 112.76 | 114.44 | C2–O5–C5 | 114.22 | 115.24 | 115.41 | 113.87 | RMSD | — | 1.168 | 1.179 | 2.219 | RMSD | — | 2.050 | 2.102 | 2.285 |
|
|
aThe experimental values are taken from references [ 22, 23]. |