- TRIPHYLITE - LiFePO₄

Theoretical atomic positions and lattice parameters at experimental volum from AMCSD

Crystal Structure

Because of the translational symmetry all the calculations are performed in the primitive unit cell and not in the conventional unit cell. The following information regarding the structure is given with respect to this primitive unit cell, which sometimes can take an unintuitive shape.

Symmetry (experimental):

Space group:	62		Pbnm
Lattice parameters (Å):	4.7138	10.3826		6.0499
Angles (°):	90	90		00

Symmetry (theoretical):

Space group:	62		Pbnm
Lattice parameters (Å):	4.7888	10.2703		6.0203
Angles (°):	90	90		90

Cell contents:

Number of atoms:	28
Number of atom types:	4
Chemical composition:	0

Atomic positions (theoretical):

Li:	0.0000	0.0000	0.0000
Fe:	0.9923	0.2714	0.2500
P:	0.4249	0.1006	0.2500
O:	0.7453	0.1069	0.2500
O:	0.1824	0.4587	0.2500
O:	0.2820	0.1717	0.0475
Li:	0.5000	0.5000	0.0000
Fe:	0.4923	0.2286	0.7500
P:	0.9249	0.3994	0.7500
O:	0.2453	0.3931	0.7500
O:	0.6824	0.0413	0.7500
O:	0.7820	0.3283	0.9525
Li:	0.0000	0.0000	0.5000
Fe:	0.0077	0.7286	0.7500
P:	0.5751	0.8994	0.7500
O:	0.2547	0.8931	0.7500
O:	0.8176	0.5413	0.7500
O:	0.7180	0.8283	0.5475
Li:	0.5000	0.5000	0.5000
Fe:	0.5077	0.7714	0.2500
P:	0.0751	0.6006	0.2500
O:	0.7547	0.6069	0.2500
O:	0.3176	0.9587	0.2500
O:	0.2180	0.6717	0.4525
O:	0.7180	0.8283	0.9525
O:	0.2180	0.6717	0.0475
O:	0.2820	0.1717	0.4525
O:	0.7820	0.3283	0.5475

Atom type

We have listed here the reduced coordinates of all the atoms in the primitive unit cell.
It is enough to know only the position of the atoms from the assymetrical unit cell and then use the symmetry to build the whole crystal structure.

Visualization of the crystal structure:

You can define the size of the supercell to be displayed in the jmol panel as integer translations along the three crystallographic axis.
Please note that the structure is represented using the primitive cell, and not the conventional one.

Powder Raman

Powder Raman spectrum

The intensity of the Raman peaks is computed within the density-functional perturbation theory. The intensity depends on the temperature (for now fixed at 300K), frequency of the input laser (for now fixed at 21834 cm^-1, frequency of the phonon mode and the Raman tensor. The Raman tensor represents the derivative of the dielectric tensor during the atomic displacement that corresponds to the phonon vibration. The Raman tensor is related to the polarizability of a specific phonon mode.

Choose the polarization of the lasers.

I ∥

I ⊥

I Total

Horizontal:

Xmin:
Xmax:

Vertical:

Ymin:
Ymax:

Data about the phonon modes

Frequency of the transverse (TO) and longitudinal (LO) phonon modes in the zone-center. The longitudinal modes are computed along the three cartesian directions. You can visualize the atomic displacement pattern corresponding to each phonon by clicking on the appropriate cell in the table below.

1	Ac	0	0	0	0
2	Ac	0	0	0	0
3	Ac	0	0	0	0
4	B1u	40	40	40	41
5	Au	49	49	49	49
6	Ag	97	97	97	97	1.873e+41 15.4	1.112e+40 0.9	1.984e+41 16.3
7	B1u	98	98	98	102
8	Au	102	102	102	113
9	B2g	113	113	113	117	4.024e+40 3.3	5.533e+40 4.6	9.557e+40 7.9
10	B1g	138	138	138	138	1.698e+37 0.0	2.335e+37 0.0	4.033e+37 0.0
11	B2u	149	149	153	149
12	Au	153	153	157	153
13	B3u	160	161	160	160
14	B2u	167	167	168	167
15	B3g	168	168	170	168	2.147e+39 0.2	2.953e+39 0.2	5.100e+39 0.4
16	B2g	170	170	171	170	2.024e+40 1.7	2.782e+40 2.3	4.806e+40 4.0
17	B1g	171	171	171	171	1.514e+39 0.1	2.035e+39 0.2	3.550e+39 0.3
18	Ag	171	171	173	171	1.095e+42 90.1	1.199e+41 9.9	1.215e+42 100.0
19	Au	173	173	181	173
20	B3u	181	185	185	181
21	B3g	185	201	193	185	3.942e+39 0.3	5.420e+39 0.4	9.361e+39 0.8
22	B2u	201	201	201	201
23	B3u	204	217	204	204
24	B1u	217	217	217	219
25	B3g	221	221	221	221	3.876e+39 0.3	5.329e+39 0.4	9.205e+39 0.8
26	Au	239	239	239	239
27	Ag	239	239	239	239	3.348e+41 27.6	1.903e+41 15.7	5.252e+41 43.2
28	B3u	239	240	239	239
29	B1g	240	241	240	240	4.231e+39 0.3	5.817e+39 0.5	1.005e+40 0.8
30	B2u	243	243	244	243
31	Ag	255	255	255	255	2.706e+40 2.2	5.773e+39 0.5	3.283e+40 2.7
32	B2g	262	262	262	262	3.344e+40 2.8	4.599e+40 3.8	7.943e+40 6.5
33	B1u	264	264	264	265
34	B1u	280	280	280	281
35	Au	281	281	281	289
36	B2g	289	289	289	297	5.121e+40 4.2	7.042e+40 5.8	1.216e+41 10.0
37	B1g	297	297	297	298	2.591e+39 0.2	3.563e+39 0.3	6.154e+39 0.5
38	B3u	298	299	298	302
39	B1u	307	307	307	308
40	B1g	308	308	308	309	9.298e+38 0.1	1.278e+39 0.1	2.208e+39 0.2
41	B3g	309	309	309	312	2.090e+39 0.2	2.874e+39 0.2	4.965e+39 0.4
42	B3u	312	313	312	313
43	B2u	313	315	315	315
44	Ag	315	320	315	320	2.756e+41 22.7	1.512e+40 1.2	2.908e+41 23.9
45	B2u	320	325	325	325
46	Au	325	348	342	331
47	B2u	375	375	376	375
48	B2g	376	376	378	376	6.260e+39 0.5	8.607e+39 0.7	1.487e+40 1.2
49	B3g	378	378	385	378	3.158e+39 0.3	4.342e+39 0.4	7.499e+39 0.6
50	B3u	385	396	388	385
51	B1u	398	398	398	402
52	Au	407	407	407	407
53	Ag	447	447	447	447	3.249e+41 26.7	9.004e+40 7.4	4.149e+41 34.2
54	B1g	453	453	453	453	6.728e+38 0.1	9.251e+38 0.1	1.598e+39 0.1
55	B3u	464	475	464	464
56	B2u	475	482	475	475
57	Au	508	508	508	508
58	B1u	509	509	509	523
59	B2u	527	527	530	527
60	Ag	530	530	533	530	3.440e+40 2.8	2.926e+38 0.0	3.469e+40 2.9
61	B3u	533	533	538	533
62	B3g	538	538	538	538	2.355e+39 0.2	3.238e+39 0.3	5.592e+39 0.5
63	B2g	539	539	539	539	7.096e+39 0.6	9.758e+39 0.8	1.685e+40 1.4
64	B1g	541	541	541	541	1.540e+39 0.1	2.117e+39 0.2	3.657e+39 0.3
65	Ag	573	573	573	573	7.309e+41 60.2	4.525e+40 3.7	7.761e+41 63.9
66	B3u	577	585	577	577
67	B2u	585	587	587	585
68	B1g	587	592	593	587	2.609e+39 0.2	3.588e+39 0.3	6.197e+39 0.5
69	B3u	851	851	851	851
70	B2u	852	852	853	852	4.381e+38 0.0	3.516e+37 0.0	4.732e+38 0.0
71	Ag	853	853	854	853	9.143e+41 75.3	7.339e+40 6.0	9.877e+41 81.3
72	B1g	857	857	857	857	1.145e+39 0.1	1.574e+39 0.1	2.719e+39 0.2
73	B1u	869	869	869	875
74	B2g	875	875	875	882	9.438e+40 7.8	1.298e+41 10.7	2.242e+41 18.5
75	Au	882	882	882	888
76	B3g	888	888	888	923	7.576e+37 0.0	1.042e+38 0.0	1.799e+38 0.0
77	B1g	953	953	953	953	4.015e+39 0.3	5.521e+39 0.5	9.536e+39 0.8
78	Ag	954	954	954	954	1.256e+41 10.3	8.972e+40 7.4	2.153e+41 17.7
79	B2u	955	955	978	955
80	Ag	978	978	984	978	6.180e+40 5.1	2.548e+40 2.1	8.728e+40 7.2
81	B3u	984	994	988	984
82	B1g	994	999	994	994	6.535e+38 0.1	8.986e+38 0.1	1.552e+39 0.1
83	B2u	999	1026	1059	999
84	B3u	1060	1072	1060	1060

No.

Char.

ω TO

ω LOx

ω LOy

ω LOz

I ∥

I ⊥