Table 2 Comparison of observed (Expt 1 = [45]; Expt 2 = [38]) and calculated IR frequencies for bulk α-FeOOH.
From: Periodic density functional theory calculations of bulk and the (010) surface of goethite
Mode | Calca | Calcb,c | Calcd | Expt 1 | Expt 2 |
|---|---|---|---|---|---|
cm-1 | (cm-1) | (cm-1) | (cm-1) | (cm-1) | (cm-1) |
O-H | 3416 | 3400 | 3227 | 3140 | 3200 |
O-H | 3411 | 3391 | 3217 | Â | Â |
O-H | 3404 | 3385 | 3213 | Â | Â |
O-H | 3396 | 3373 | 3206 | Â | Â |
δ(OH) | 954 | 974 | 1011 |  | 1000 |
δ(OH) | 930 | 966 | 1007 |  |  |
δ(OH) | 901 | 958 | 958 |  |  |
δ(OH) | 896 | 911 | 956 |  |  |
γ(OH) | 839 | 857 | 934 | 893 | 887 |
γ(OH) | 810 | 848 | 896 |  |  |
γ(OH) | 806 | 830 | 892 |  |  |
γ(OH) | 797 | 819 | 888 | 793 |  |
Fe-Os | 599 | 576 | 640 | 620 | 610 |
Fe-Os | 547 | 567 | 623 | Â | Â |
Fe-Os | 525 | 558 | 540 | Â | Â |
Fe-Os | 482 | 547 | 538 | Â | Â |
δ(Fe-O-Fe) | 467 | 477 | 526 | 495 |  |
δ(Fe-O-Fe) | 424 | 461 | 481 |  |  |
δ(Fe-O-Fe) | 417 | 453 | 459 |  |  |
δ(Fe-O-Fe) | 395 | 441 | 442 |  |  |
Fe-Oas | 391 | 426 | 410 | 405 | Â |
Fe-Oas | 376 | 413 | 405 | Â | Â |
Fe-Oas | 371 | 397 | 401 | Â | Â |
Fe-Oas | 357 | 413 | 399 | Â | Â |
O lattice | 348 | 379 | 396 | Â | Â |
O lattice | 345 | 372 | 395 | Â | Â |
O lattice | 343 | 365 | 380 | Â | Â |
O lattice | 321 | 361 | 375 | Â | Â |
Fe-O-Fe | 309 | 354 | 360 | Â | Â |
Fe-O-Fe | 293 | 338 | 334 | Â | Â |
Fe-O-Fe | 284 | 328 | 307 | Â | Â |
Fe-O-Fe | 268 | 314 | 301 | Â | Â |
Fe-O-Fe | 258 | 309 | 293 | Â | Â |
Fe-O-Fe | 254 | 301 | 288 | Â | Â |
Fe-O-Fe | 242 | 287 | 270 | Â | Â |
Fe-O-Fe | 228 | 274 | 266 | Â | Â |
Fe---Fe | 223 | 262 | 255 | Â | Â |
Fe---Fe | 211 | 246 | 241 | Â | Â |
Fe---Fe | 179 | 243 | 237 | Â | Â |
Fe---Fe | 174 | 240 | 206 | Â | Â |
FeO6 rock | 143 | 230 | 185 | Â | Â |
FeO6 | 108 | 210 | 163 | Â | Â |
FeO6 | 78 | 177 | 132 | Â | Â |
FeO6 | 69 | 164 | 117 | Â | Â |
Tunnel Distortion | 24 | 143 | --- | Â | Â |