Table 1. Lattice constants (a, b and c), Si-Si bond length (dSi-Si), Si-H bond length (dSi-H), Si-Si-Si bond angle (θSi-Si-Si), Si-Si-H bond angle (θSi-Si-H), total energy (ET), unit cell volume (V), band gap energy (Eg), and binding energy (Eb) of B- configuration of hydrogenated silicene under different pressures.
|
|
Pressure (GPa)
|
Parame-ters
|
0
|
3
|
6
|
9
|
12
|
15
|
18
|
21
|
This work
|
Rep. [33]
|
This work
|
a (Aͦ)
|
6.40
|
6.32
|
6.29
|
6.10
|
5.91
|
5.82
|
5.65
|
5.68
|
5.74
|
b (Aͦ)
|
3.85
|
3.82
|
3.78
|
3.79
|
3.71
|
3.59
|
3.61
|
3.50
|
3.611
|
c (Aͦ)
|
6.20
|
|
5.75
|
4.95
|
4.93
|
4.90
|
4.07
|
4.01
|
3.98
|
dSi-Si
(Aͦ)
|
2.36, 2.36
|
2.36
|
2.34, 2.33
|
2.35, 2.32
|
2.30, 2.29
|
2.27, 2.30
|
2.30, 2.24
|
2.28, 2.32
|
2.32, 2.29
|
dSi-H (Aͦ)
|
1.51
|
1.5
|
1.52
|
1.496
|
1.49
|
1.48
|
1.45
|
1.44
|
1.41
|
ϴSi-Si-Si
(degree)
|
110.80, 109.68
|
110
|
110.22, 108.47
|
109.37, 107.60
|
106.60, 107.29
|
105.40, 104.49
|
104.71, 103.27
|
103.20, 99.94
|
102.36, 98.19
|
ϴSi-Si-H
(degree)
|
107.66
|
|
108.18
|
109.07
|
110.26
|
112.70
|
113.12
|
114.81
|
115.54
|
ET (eV)
|
-744.33
|
|
-741.74
|
-739.81
|
-737.75
|
-735.67
|
-734.30
|
-732.56
|
-731.18
|
V (Å3)
|
152.97
|
|
136.89
|
114.46
|
107.92
|
102.45
|
83.10
|
83.05
|
78.98
|
Eg (eV)
|
1.663
|
1.6
|
1.557
|
1.01
|
0.60
|
0.13
|
0.04
|
0.01
|
0.00
|
Eb (eV)
|
2.992
|
|
2.345
|
1.86
|
1.346
|
0.827
|
0.46
|
0.05
|
-0.29
|
Table 2. The structural parameters of C- configuration of hydrogenated silicene under different pressures.
Parameter
|
|
Pressure (GPa)
|
0
|
3
|
6
|
9
|
12
|
15
|
18
|
21
|
|
This work
|
Rep. [33]
|
This work
|
a = b (Aͦ)
|
3.83
|
3.82
|
3.81
|
3.77
|
3.75
|
3.72
|
3.70
|
3.64
|
3.61
|
c (Aͦ)
|
4.96
|
|
4.32
|
4.097
|
3.942
|
3.836
|
3.75
|
3.23
|
3.20
|
dSi-Si (Aͦ)
|
2.32
|
2.16
|
2.31
|
2.289
|
2.274
|
2.26
|
2.25
|
2.22
|
2.18
|
dSi-H (Aͦ)
|
1.50
|
1.50
|
1.49
|
1.491
|
1.486
|
1.483
|
1.48
|
1.47
|
1.47
|
ϴSi-Si-Si
(degree)
|
111.15
|
112.00
|
112.10
|
113.09
|
114.97
|
115.82
|
116.73
|
118
|
119.99
|
ϴSi-Si-H
(degree)
|
107.72
|
|
106.75
|
105.79
|
107.92
|
108.07
|
108.18
|
89.99
|
89.84
|
ET (eV)
|
-247.30
|
|
-247.30
|
-247.20
|
-247.1
|
-246.9
|
-246.8
|
-246.5
|
-245.90
|
V (Å3)
|
69.40
|
|
54.26
|
50.42
|
47.95
|
46.025
|
44.4
|
41.29
|
40.11
|
Eg (eV)
|
1.96
|
2.00
|
1.54
|
1.38
|
0.94
|
0.59
|
0.29
|
0.02
|
00
|
Eb (eV)
|
3.036
|
|
2.332
|
1.854
|
1.390
|
0.921
|
0.479
|
0.094
|
-0.29
|
Table 3 The conductivity threshold (Eth), static dielectric constant ε(0), static refractive index n(0), birefringence Δn(0) and plasmon energy (ћωp) of B- configuration of hydrogenated silicene under 0 GPa, 6 GPa and 12 GPa external pressures.
Parameter
|
0 GPa
|
6 GPa
|
12 GPa
|
|
E⊥c
|
E||c
|
E⊥c
|
E||c
|
E⊥c
|
E||c
|
Eth (eV)
|
2.205
|
3.646
|
1.243
|
2.498
|
0.88
|
1.549
|
ε(0)
|
6.115
|
3.851
|
8.140
|
5.373
|
9.750
|
6.157
|
n
|
2.472
|
1.962
|
2.853
|
2.318
|
3.122
|
2.481
|
Δn
|
0.510
|
|
0.534
|
|
0.641
|
|
|
15.223
|
15.104
|
16.962
|
16.842
|
17.713
|
17.395
|