Structural details of \mathrm{La}_{2} \mathrm{CoMnO}_{6} obtained at different temperatures from NPD (D1B, ILL) data using the P 2_{1} / n structural model freeing only the mode-amplitude (see the text): \mathrm{GM}_{4}{ }^{+}, \mathrm{X}_{3}{ }^{+}and \mathrm{X}_{5}{ }^{+}. \mathrm{Mn} / \mathrm{Co} atoms occupy the site 2 \mathrm{a}(0,0,0), \mathrm{Co} / \mathrm{Mn} atoms occupy the site 2 \mathrm{ b}(0,0,1 / 2), \mathrm{La} atoms occupy the site 4 \mathrm{e}(x, y, z) and O atoms occupy the site 4 \mathrm{e}(x, y, z)
| Temperatures | 2 K | 50 K | 100 K | 150 K | 200 K | 250 K | 300 K | |
|---|---|---|---|---|---|---|---|---|
| La | x | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
| y | 0.5213(3) | 0.5218(3) | 0.5229(2) | 0.5222(2) | 0.5215(2) | 0.5206(3) | 0.5211(3) | |
| z | 0.2500 | 0.2500 | 0.25000 | 0.2500 | 0.2500 | 0.2500 | 0.2500 | |
| B_{\text {iso }}\left(\AA^{2}\right) | 0.58(3) | 0.58(3) | 0.60(1) | 0.71(1) | 0.83(4) | 0.88(1) | 0.61(1) | |
| O1 | x | -0.7753(1) | -0.7748(7) | -0.7765(5) | -0.7740(5) | -0.7737(6) | -0.7739(6) | -0.7778(6) |
| y | 0.2757(1) | 0.2752(7) | 0.2735(5) | 0.2733(5) | 0.2736(6) | 0.2726(6) | 0.2697(6) | |
| z | 0.0354(1) | 0.0353(1) | 0.0348(1) | 0.0344(1) | 0.0342(1) | 0.0341(1) | 0.0340(1) | |
| B_{\text {iso }}\left(\AA^{2}\right) | 0.61(1) | 0.61(1) | 0.68(3) | 0.74(1) | 0.78(2) | 0.91(1) | 0.82(2) | |
| O2 | x | -0.5709(2) | -0.5707(2) | -0.5696(16) | -0.5688(2) | -0.5684(2) | -0.5682(2) | -0.5681(2) |
| y | 0.5091(3) | 0.5093(3) | 0.5097(2) | 0.5094(2) | 0.5091(2) | 0.5088(3) | 0.5089(3) | |
| z | -0.2528 | -0.2528 | -0.2528 | -0.2528 | -0.2528 | -0.2528 | -0.2528 | |
| B_{\text {iso }}\left(\AA^{2}\right) | 0.61(1) | 0.61(1) | 0.68(3) | 0.74(1) | 0.78(2) | 0.91(1) | 0.82(2) | |
| O3 | x | -0.2696(1) | -0.2691(7) | -0.2707(5) | -0.2683(5) | -0.2680(6) | -0.2682(6) | -0.2721(6) |
| y | 0.2186(1) | 0.2191(7) | 0.2208(5) | 0.2210(5) | 0.2207(6) | 0.2217(6) | 0.2246(6) | |
| z | -0.0354(1) | -0.0353(1) | -0.0348(1) | -0.0344(1) | -0.0342(1) | -0.0341(1) | -0.0340(1) | |
| B_{\text {iso }}\left(\AA^{2}\right) | 0.61(1) | 0.61(1) | 0.68(3) | 0.74(1) | 0.78(2) | 0.91(1) | 0.82(2) | |
| Mn/Co | 2a | 0.28(1)/0.72(1) | 0.28(1)/0.72(1) | 0.28(1)/0.72(1) | 0.28(1)/0.72(1) | 0.28(1)/0.72(1) | 0.28(1)/0.72(1) | 0.28(1)/0.72(1) |
| Co/Mn | 2b | 0.72(1)/0.28(1) | 0.72(1)/0.28(1) | 0.72(1)/0.28(1) | 0.72(1)/0.28(1) | 0.72(1)/0.28(1) | 0.72(1)/0.28(1) | 0.72(1)/0.28(1) |
| Cell parameters | a(\AA) | 5.5029(1) | 5.5034(1) | 5.5048(2) | 5.5065(1) | 5.5084(1) | 5.5112(1) | 5.5128(1) |
| b(\AA) | 5.4669(1) | 5.4672(2) | 5.4672(2) | 5.4675(3) | 5.4692(1) | 5.4702(1) | 5.4714(3) | |
| c(\AA) | 7.7435(1) | 7.7438(1) | 7.7431(8) | 7.7456(1) | 7.7473(5) | 7.7493(1) | 7.7526(1) | |
| \beta\left({ }^{\circ}\right) | 90.081(1) | 90.053(1) | 90.087(1) | 90.081(1) | 90.105(1) | 90.135(1) | 90.08(1) | |
| V\left(\AA^{3}\right) | 232.96(5) | 233.00(1) | 233.03(2) | 233.19(1) | 233.40(3) | 233.62(1) | 233.84(1) | |
| Reliability factors | R_{\mathrm{p}}(\%) | 2.75 | 2.63 | 2.25 | 2.14 | 2.18 | 2.33 | 1.57 |
| R_{\mathrm{wp}} (%) | 4.42 | 4.20 | 3.67 | 3.52 | 3.52 | 3.81 | 2.09 | |
| R_{\text {exp }} (%) | 0.85 | 1.13 | 0.85 | 1.13 | 1.13 | 1.13 | 0.90 | |
| \chi^{2} | 5.2 | 5.8 | 5.2 | 5.71 | 5.67 | 4.2 | 5.32 | |
| R_{\text {Bragg }} | 4.5 | 5.1 | 4.01 | 4.67 | 5.10 | 3.5 | 4.89 |