Silicide carbides or carbide silicides are compounds containing anions composed of silicide (Si4−) and carbide (C4−) or clusters therof. They can be considered as mixed anion compounds or intermetallic compounds, as silicon could be considered as a semimetal.
Related compounds include the germanide carbides, phosphide silicides, boride carbides and nitride carbides. Other related compounds may contain more condensed anion combinations such as the carbidonitridosilicates with C(SiN3)4 with N bridging between two silicon atoms.[1]
Silicide carbide compounds can be made by heating silicon, graphite, and metal together. It is important to exclude oxygen before and during the reaction.[2] The flux method involves a reaction in a molten metal. Gallium is suitable, because it dissolves carbon and silicon, but does not react with them.[3]
Silicide carbides are a kind of ceramic, yet they also have metallic properties. They are not as brittle as most ceramics, but are stiffer than metals. They have high melting temperatures.[4]
In air silicide carbide compounds are stable, and are hardly affected by water. The appearance is often metallic grey. When powdered the colour is dark grey.[5]
When ErFe2SiC is dissolved in acid, mostly methane is produced, but the products include some hydrocarbons with two and three carbon atoms.[5]
The lanthanide contraction is evident with the cell sizes for rare earth element silicide carbides.[5]
formula | system | space group | unit cell Å | volume | density | comment | ref |
---|---|---|---|---|---|---|---|
Ti3SiC2 | hexagonal | P63/mmc | a = 3.064 c = 17.65 Z=2 | 143.5 | 4.53 | mp 2300°C | [6] |
Ti5Si3Cx | [4] | ||||||
Y3Si2C2 | orthorhombic | Cmmm | a=3.845 b=15.634 c=4.213 | 253.3 | Pauli paramagnetic
grey metallic air stable |
[7] | |
Y5Si3C1.8 | [8] | ||||||
Y1.8C2Si8(B12)3 | rhombohedral | R3m | a=10.101, c=16.441, Z=3 | 1452.7 | 1.551 | [3] | |
YCr2Si2C | tetragonal | P4/mmm | a=3.998 c=5.289 Z=1 | Pauli paramagnetic
grey metallic |
[9] | ||
YCr3Si2C | [10] | ||||||
YMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
YFe2SiC | orthorhombic | Cmcm | Z=4 | 270 | grey metallic
air stable |
[5] | |
YRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Ba3Si4C2 | tetragonal | I4/mcm | a = 8.7693 c = 12.3885 | semiconductor; contains [Si4]4− and [C2]2− | [12] | ||
La3Si2C2 | orthorhombic | Cmmm | a=4.039,b=16.884, and c=4.506 | 307.3 | grey metallic
air stable |
[7] | |
LaCr2Si2C | tetragonal | P4/mmm | a=4.037 c=5.347 Z=1 | [9] | |||
La2Fe2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
Ce3Si2C2 | orthorhombic | Cmmm | a=3.990 b=16.592 c= 4.434 | 293.5 | grey metallic
air stable ?ferromagnetic (TC=10K |
[7] | |
CeCr2Si2C | tetragonal | P4/mmm | a=4.020 c=5.284 Z=1 | grey metallic | [9] | ||
Ce2Fe2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
CeMo2Si2C | [14] | ||||||
CeRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Pr3Si2C2 | orthorhombic | Cmmm | a=3.967 b=16.452 c=4.399 | 287.1 | grey metallic
air stable ferromagnetic TC=25K |
[7] | |
PrCr2Si2C | tetragonal | P4/mmm | a=4.022, c = 5.352 Z=1 | 86.58 | 6.00 | grey metallic
Si-Si pair bond 2.453 Å |
[9] |
PrMo2Si2C | tetragonal | P4/mmm | a=4.2139 c=5.4093 Z=1 | 96.1 | metallic dark grey | [15] | |
PrRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Nd3Si2C2 | orthorhombic | Cmmm | a=3.949 b=16.303 c=4.375 | 281.7 | grey metallic
air stable ferromagnetic TC=30K |
[7] | |
NdCr2Si2C | tetragonal | P4/mmm | a=4.026 c=5.336 Z=1 | grey metallic | [9] | ||
NdRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Sm3Si2C2 | orthorhombic | Cmmm | a=3.913 b=16.073 c=4.316 | 271.4 | grey metallic
air stable antiferromagnetic TN=19K |
[7] | |
SmCr2Si2C | tetragonal | P4/mmm | a=4.011 c=5.321 Z=1 | grey metallic | [9] | ||
SmMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
SmFe2SiC | orthorhombic | Cmcm | Z=4 | 278 | grey metallic
air stable |
[5] | |
Sm2Fe2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
SmRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Gd3Si2C2 | orthorhombic | Cmmm | a=3.886 b=15.863 c=4.726 | grey metallic
air stable antiferromagnetic TN=50K |
[7] | ||
GdCr2Si2C | tetragonal | P4/mmm | a=4.007 c=5.324 Z=1 | 263.6 | grey metallic | [9] | |
GdCr3Si2C | hexagonal | P6/mmm | [10] | ||||
GdMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
GdFe2SiC | orthorhombic | Cmcm | Z=4 | 273 | grey metallic
air stable |
[5] | |
GdRu2SiC | orthorhombic | Cmcm | a = 3.830, b = 11.069, c = 7.157 Z=4 | 303.4 | 8.745 | silvery
air stable |
[11][16] |
Tb3Si2C2 | orthorhombic | Cmmm | a=3.854 c=15.702 c=4.236 | 256.3 | grey metallic
air stable antiferromagnetic TN=28K |
[7] | |
Tb1.8C2Si8(B12)3 | rhombohedral | R3m | a=10.1171, c=16.397, Z=3 | 1453.4 | 1.583 | [3] | |
TbCr2Si2C | tetragonal | P4/mmm | a=4.002 c=5.314 Z=1 | grey metallic | [9] | ||
TbCr3Si2C | hexagonal | P6/mmm | [10] | ||||
TbMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
TbFe2SiC | orthorhombic | Cmcm | Z=4 | 270 | grey metallic
air stable |
[5] | |
TbRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Dy3Si2C2 | orthorhombic | Cmmm | a=3.838 b=15.611 c=4.203 | 251.8 | grey metallic
air stable antiferromagnetic TN=30K |
[7] | |
DyCr2Si2C | tetragonal | P4/mmm | a=3.999 c=5.306 Z=1 | grey metallic | [9] | ||
DyCr3Si2C | hexagonal | P6/mmm | [10] | ||||
DyMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Dy2Fe2Si2C | monoclinic | C2/m | grey metallic
air stable |
[7] | |||
DyFe2SiC | orthorhombic | Cmcm | Z=4 | 269 | grey metallic
air stable |
[17] | |
DyRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Ho3Si2C2 | orthorhombic | Cmmm | a=3.828 b=15.507 c=4.189 | 248.7 | grey metallic
air stable metamagnetic TN=14K |
[7] | |
HoCr2Si2C | tetragonal | P4/mmm | a=3.996 c=5.274 Z=1 | grey metallic | [9] | ||
HoCr3Si2C | hexagonal | P6/mmm | [10] | ||||
HoMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
HoFe2SiC | orthorhombic | Cmcm | Z=4 | 267 | grey metallic
air stable |
[5] | |
HoRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Er3Si2C2 | orthorhombic | Cmmm | a=3.811 b=15.420 c=4.172 | 245.2 | grey metallic
air stable metamagnetic |
[7] | |
Er1.8C2Si8(B12)3 | rhombohedral | R3m | a=10.0994, c=16.354, Z=3 | 1444.6 | 1.619 | [3] | |
ErCr3Si2C | hexagonal | P6/mmm | [10] | ||||
ErMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
ErFe2SiC | orthorhombic | Cmcm | Z=4 | 265 | grey metallic
air stable |
[5] | |
ErRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Tm3Si2C2 | orthorhombic | Cmmm | a=3.796, b=15.328, c=4.145 | grey metallic
air stable metamagnetic |
[7] | ||
TmCr3Si2C | hexagonal | P6/mmm | [10] | ||||
TmMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
TmFe2SiC | orthorhombic | Cmcm | Z=4 | 263 | grey metallic
air stable |
[5] | |
Tm2Fe2Si2C | monoclinic | C2/m | a = 10.497, b = 3.882, c = 6.646, β = 128.96° | antiferromagnetic at TN = 2.7 K
metallic |
[17] | ||
TmRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
LuCr3Si2C | hexagonal | P6/mmm | [10] | ||||
LuMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
LuFe2SiC | orthorhombic | Cmcm | Z=4 | 261 | grey metallic
air stable |
[5] | |
Lu2Fe2Si2C | monoclinic | C2/m | Pauli paramagnetic
metallic |
[17] | |||
YRe2SiC | orthorhombic | Cmcm | Z=4 | superconductor Tc ≈ 5.9 K | [11][18] | ||
Y2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
La2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
CeRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Ce2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
PrRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
NdRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Nd2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
SmRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Sm2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
GdRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Gd2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
TbRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Tb2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
DyRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Dy2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
HoRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Ho2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
ErRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Er2Re2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
TmRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
YOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
LaOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
CeOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
PrOs2SiC | orthorhombic | Cmcm | a=3.9602,b=11.058,c=7.172 Z=4 | [11] | |||
NdOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
SmOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
GdOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
TbOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
DyOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
HoOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
ErOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
TmOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
ThCr2Si2C | tetragonal | [19] | |||||
ThMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
ThFe2SiC | orthorhombic | Cmcm | a = 3.8632, b = 10.806, c = 6.950 Z=4 | 290 | 8.79 | grey metallic
air stable |
[5] |
Th2Fe2Si2C | monoclinic | C2/m | Z=2 | [13] | |||
ThFe10SiC2-x | tetragonal | a = 10.053 and c = 6.516 | [17] | ||||
ThMo2Si2C | tetragonal | P4/mmm | a = 4.2296 c = 5.3571 Z=1 | 95.84 | superconductor Tc=2.2K | [20] | |
ThRu2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
ThRe2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
Th2Re2Si2C | monoclinic | C2/m | a=11.1782, b=4.1753, c=7.0293, β=128.721° Z=2 | [13] | |||
ThOs2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
U3Si2C2 | tetrahedral | I4/mmm | a=3.5735 c=18.882 Z=2 | 241.1 | 10.94 | C-Si bond 1.93 Å
Spin glass freeze at 28K grey metallic air stable |
[2][21] |
U20Si16C3 | hexagonal | P6/mmm | a= 10.377, c= 8.005, Z= 1 | 746.5 | 11.67 | grey metallic
air stable |
[2] |
UCr2Si2C | tetragonal | P4/mmm | a =3.983 c =5.160 Z=1 | 81.84 | 8.32 | [22] | |
UCr3Si2C | hexagonal | P6/mmm | [10] | ||||
UMn2SiC | orthorhombic | Cmcm | Z=4 | [11] | |||
UFe2SiC | orthorhombic | Cmcm | Z=4 | 268 | grey metallic
air stable |
[5] | |
U2MoSi2C | tetragonal | P4/mbm | a = 6.67 c = 4.33 | [23] | |||
UOs2SiC | orthorhombic | Cmcm | Z=4 | [11] |