-    SYNGENITE     -    K2CaSO4H2O

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:  11  P2_1/m 
Lattice parameters (Å):  9.7700  7.1500  6.2500 
Angles (°):  90  104.0  90 

Symmetry (theoretical): 

Space group:  11  P2_1/m 
Lattice parameters (Å):  9.8021  6.9739  6.3169 
Angles (°):  90  101.17  90 

Cell contents: 

Number of atoms:  32 
Number of atom types:  5 
Chemical composition:  0 

Atomic positions (theoretical):

K:  0.3050  0.0106  0.1529 
Ca:  0.9620  0.2500  0.3419 
S:  0.9886  0.2500  0.8385 
S:  0.6453  0.2500  0.3336 
O:  0.1216  0.2500  0.9897 
O:  0.2161  0.2500  0.4752 
O:  0.5098  0.2500  0.1853 
O:  0.6293  0.2500  0.5594 
O:  0.7287  0.0797  0.2901 
O:  0.8757  0.2500  0.9629 
O:  0.9732  0.0806  0.6942 
H:  0.2436  0.3650  0.5678 
K:  0.6950  0.5106  0.8471 
Ca:  0.0380  0.7500  0.6581 
S:  0.0114  0.7500  0.1615 
S:  0.3547  0.7500  0.6664 
O:  0.8784  0.7500  0.0103 
O:  0.7839  0.7500  0.5248 
O:  0.4902  0.7500  0.8147 
O:  0.3707  0.7500  0.4406 
O:  0.2713  0.5797  0.7099 
O:  0.1243  0.7500  0.0371 
O:  0.0268  0.5806  0.3058 
H:  0.7564  0.8650  0.4322 
K:  0.6950  0.9894  0.8471 
O:  0.2713  0.9203  0.7099 
O:  0.0268  0.9194  0.3058 
H:  0.7564  0.6350  0.4322 
K:  0.3050  0.4894  0.1529 
O:  0.7287  0.4203  0.2901 
O:  0.9732  0.4194  0.6942 
H:  0.2436  0.1350  0.5678 
Atom type  X  Y  Z 

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: 

Size:

 Nx:  Ny:  Nz: 
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
Au
-22
-22
0
-22
2
ac
0
0
0
0
3
ac
0
0
0
0
4
ac
0
0
7
0
5
Bg
34
34
34
34
3.367e+37
0.0
4.630e+37
0.1
7.998e+37
0.1
6
Bu
65
67
65
67
7
Ag
67
75
67
71
2.865e+38
0.4
2.750e+38
0.4
5.615e+38
0.7
8
Ag
77
77
77
77
2.551e+39
3.3
8.353e+38
1.1
3.386e+39
4.4
9
Au
79
79
79
79
10
Bg
79
79
79
79
3.998e+37
0.1
5.497e+37
0.1
9.494e+37
0.1
11
Bg
88
88
88
88
2.581e+38
0.3
3.066e+38
0.4
5.647e+38
0.7
12
Bu
89
90
89
90
13
Ag
98
98
98
98
2.717e+38
0.4
2.828e+38
0.4
5.544e+38
0.7
14
Ag
100
100
100
100
8.271e+38
1.1
5.277e+38
0.7
1.355e+39
1.8
15
Au
106
106
107
106
16
Bg
111
111
111
111
17
Bu
114
115
114
121
18
Bu
121
121
121
124
19
Ag
124
124
124
127
5.429e+38
0.7
2.560e+38
0.3
7.989e+38
1.0
20
Au
127
127
129
130
21
Ag
130
130
130
133
3.079e+38
0.4
6.545e+37
0.1
3.733e+38
0.5
22
Ag
133
133
133
139
1.704e+38
0.2
1.204e+38
0.2
2.909e+38
0.4
23
Bg
139
139
139
145
2.173e+38
0.3
2.418e+38
0.3
4.591e+38
0.6
24
Au
148
148
149
148
25
Bg
159
159
159
159
8.337e+37
0.1
8.858e+37
0.1
1.720e+38
0.2
26
Bu
160
160
160
161
27
Bg
170
170
170
170
2.811e+38
0.4
4.458e+38
0.6
7.268e+38
0.9
28
Au
171
171
171
171
29
Bu
174
174
174
174
30
Ag
175
175
175
175
2.000e+39
2.6
1.457e+37
0.0
2.015e+39
2.6
31
Ag
181
181
181
181
9.097e+38
1.2
1.023e+37
0.0
9.199e+38
1.2
32
Bu
187
188
187
187
33
Au
188
189
188
188
34
Ag
189
194
189
189
1.480e+38
0.2
8.963e+37
0.1
2.377e+38
0.3
35
Bg
200
200
200
200
9.542e+37
0.1
1.312e+38
0.2
2.266e+38
0.3
36
Bu
204
207
204
205
37
Ag
207
208
207
207
4.755e+38
0.6
1.800e+38
0.2
6.554e+38
0.8
38
Bu
208
210
208
210
39
Bg
210
212
210
212
6.145e+37
0.1
1.028e+38
0.1
1.642e+38
0.2
40
Au
212
219
219
213
41
Bg
219
225
225
219
1.730e+39
2.2
1.849e+39
2.4
3.579e+39
4.6
42
Au
225
238
231
225
43
Bg
252
252
252
252
2.157e+38
0.3
3.602e+38
0.5
5.758e+38
0.7
44
Au
266
266
273
266
45
Ag
273
273
276
273
2.327e+38
0.3
1.376e+38
0.2
3.703e+38
0.5
46
Bu
276
285
296
282
47
Ag
300
300
300
300
1.721e+38
0.2
1.703e+38
0.2
3.423e+38
0.4
48
Bu
300
306
300
334
49
Bg
420
420
420
420
2.825e+39
3.7
3.447e+39
4.5
6.273e+39
8.1
50
Au
428
428
430
428
51
Bg
431
431
431
431
2.718e+39
3.5
3.531e+39
4.6
6.249e+39
8.1
52
Au
434
434
434
434
53
Ag
450
450
450
450
3.330e+39
4.3
2.935e+39
3.8
6.265e+39
8.1
54
Bu
450
450
450
450
55
Ag
484
484
484
484
3.309e+39
4.3
2.500e+39
3.2
5.809e+39
7.5
56
Bu
497
497
497
497
57
Ag
587
587
587
587
1.853e+39
2.4
1.846e+39
2.4
3.699e+39
4.8
58
Bu
589
589
589
589
59
Bu
589
590
590
590
60
Au
590
592
593
590
61
Bg
593
593
595
593
2.456e+39
3.2
3.585e+39
4.6
6.041e+39
7.8
62
Bu
595
595
595
595
63
Ag
595
596
599
598
2.211e+39
2.9
2.816e+39
3.7
5.027e+39
6.5
64
Bu
613
614
613
614
65
Bg
614
616
614
614
2.526e+39
3.3
3.798e+39
4.9
6.324e+39
8.2
66
Ag
616
618
616
616
1.762e+39
2.3
1.345e+39
1.7
3.108e+39
4.0
67
Bu
645
645
645
648
68
Ag
648
648
648
653
1.263e+39
1.6
1.064e+39
1.4
2.327e+39
3.0
69
Au
728
728
728
728
70
Bg
728
728
744
728
1.699e+38
0.2
2.279e+38
0.3
3.977e+38
0.5
71
Bu
859
860
859
860
72
Au
860
861
860
860
73
Bg
861
867
861
861
6.890e+38
0.9
1.147e+39
1.5
1.836e+39
2.4
74
Ag
867
875
867
867
2.186e+38
0.3
8.419e+37
0.1
3.028e+38
0.4
75
Bu
949
951
949
949
76
Ag
951
951
951
951
6.121e+40
79.4
4.944e+38
0.6
6.170e+40
80.0
77
Bu
988
988
988
988
78
Ag
991
991
991
991
5.340e+40
69.2
7.301e+38
0.9
5.413e+40
70.2
79
Bg
1016
1016
1016
1016
1.838e+39
2.4
2.063e+39
2.7
3.901e+39
5.1
80
Au
1017
1017
1037
1017
81
Au
1067
1067
1108
1067
82
Bu
1108
1112
1112
1110
83
Ag
1112
1120
1120
1112
2.378e+39
3.1
2.033e+39
2.6
4.412e+39
5.7
84
Bg
1120
1129
1129
1120
2.388e+39
3.1
3.926e+39
5.1
6.313e+39
8.2
85
Ag
1129
1131
1132
1129
5.562e+39
7.2
3.939e+39
5.1
9.501e+39
12.3
86
Bu
1132
1149
1132
1138
87
Bu
1157
1158
1157
1158
88
Ag
1158
1175
1158
1176
2.206e+39
2.9
2.293e+39
3.0
4.499e+39
5.8
89
Ag
1176
1176
1176
1202
4.786e+39
6.2
4.768e+39
6.2
9.554e+39
12.4
90
Bu
1207
1216
1207
1221
91
Ag
1600
1600
1600
1600
1.959e+38
0.3
2.521e+38
0.3
4.480e+38
0.6
92
Bu
1602
1602
1602
1604
93
Au
3137
3137
3137
3137
94
Bg
3137
3137
3148
3137
1.362e+40
17.7
1.593e+40
20.7
2.955e+40
38.3
95
Ag
3148
3148
3152
3148
6.522e+40
84.6
1.190e+40
15.4
7.711e+40
100.0
96
Bu
3152
3153
3186
3160
No.  Char.  ω TO  ω LOx  ω LOy  ω LOz  I ∥  I ⊥  I Total 

You can define the size of the supercell for the visualization of the vibration.

Nx: 
Ny: 
Nz: 
Normalized
Raw
Options for intensity.