Point Group C18h



C18h E 2C18 2C9 2C6 2(C9)2 2(C18)5 2C3 2(C18)7 2(C9)4 C2 i 2(S9)13 2(S18)7 2S3 2(S18)5 2(S9)11 2S6 2S9 2S18 σh
Ag 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Bg 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1
E1g* 2 1.8794 1.5321 1 0.3473 -0.3473 -1 -1.5321 -1.8794 -2 2 1.8794 1.5321 1 0.3473 -0.3473 -1 -1.5321 -1.8794 -2
E2g* 2 1.5321 0.3473 -1 -1.8794 -1.8794 -1 0.3473 1.5321 2 2 1.5321 0.3473 -1 -1.8794 -1.8794 -1 0.3473 1.5321 2
E3g* 2 1 -1 -2 -1 1 2 1 -1 -2 2 1 -1 -2 -1 1 2 1 -1 -2
E4g* 2 0.3473 -1.8794 -1 1.5321 1.5321 -1 -1.8794 0.3473 2 2 0.3473 -1.8794 -1 1.5321 1.5321 -1 -1.8794 0.3473 2
E5g* 2 -0.3473 -1.8794 1 1.5321 -1.5321 -1 1.8794 0.3473 -2 2 -0.3473 -1.8794 1 1.5321 -1.5321 -1 1.8794 0.3473 -2
E6g* 2 -1 -1 2 -1 -1 2 -1 -1 2 2 -1 -1 2 -1 -1 2 -1 -1 2
E7g* 2 -1.5321 0.3473 1 -1.8794 1.8794 -1 -0.3473 1.5321 -2 2 -1.5321 0.3473 1 -1.8794 1.8794 -1 -0.3473 1.5321 -2
E8g* 2 -1.8794 1.5321 -1 0.3473 0.3473 -1 1.5321 -1.8794 2 2 -1.8794 1.5321 -1 0.3473 0.3473 -1 1.5321 -1.8794 2
Au 1 1 1 1 1 1 1 1 1 1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
Bu 1 -1 1 -1 1 -1 1 -1 1 -1 -1 1 -1 1 -1 1 -1 1 -1 1
E1u* 2 1.8794 1.5321 1 0.3473 -0.3473 -1 -1.5321 -1.8794 -2 -2 -1.8794 -1.5321 -1 -0.3473 0.3473 1 1.5321 1.8794 2
E2u* 2 1.5321 0.3473 -1 -1.8794 -1.8794 -1 0.3473 1.5321 2 -2 -1.5321 -0.3473 1 1.8794 1.8794 1 -0.3473 -1.5321 -2
E3u* 2 1 -1 -2 -1 1 2 1 -1 -2 -2 -1 1 2 1 -1 -2 -1 1 2
E4u* 2 0.3473 -1.8794 -1 1.5321 1.5321 -1 -1.8794 0.3473 2 -2 -0.3473 1.8794 1 -1.5321 -1.5321 1 1.8794 -0.3473 -2
E5u* 2 -0.3473 -1.8794 1 1.5321 -1.5321 -1 1.8794 0.3473 -2 -2 0.3473 1.8794 -1 -1.5321 1.5321 1 -1.8794 -0.3473 2
E6u* 2 -1 -1 2 -1 -1 2 -1 -1 2 -2 1 1 -2 1 1 -2 1 1 -2
E7u* 2 -1.5321 0.3473 1 -1.8794 1.8794 -1 -0.3473 1.5321 -2 -2 1.5321 -0.3473 -1 1.8794 -1.8794 1 0.3473 -1.5321 2
E8u* 2 -1.8794 1.5321 -1 0.3473 0.3473 -1 1.5321 -1.8794 2 -2 1.8794 -1.5321 1 -0.3473 -0.3473 1 -1.5321 1.8794 -2


Additional information

Number of symmetry elements h = 36
Number of classes, irreps n = 36
Number of real-valued irreducible representations n = 20
Abelian group yes
Optical Isomerism (Chirality) no
Polar no
Parity yes


Reduce representation to irreducible representations


E 2C18 2C9 2C6 2(C9)2 2(C18)5 2C3 2(C18)7 2(C9)4 C2 i 2(S9)13 2(S18)7 2S3 2(S18)5 2(S9)11 2S6 2S9 2S18 σh



Genrate representation from irreducible representations


Ag Bg E1g* E2g* E3g* E4g* E5g* E6g* E7g* E8g* Au Bu E1u* E2u* E3u* E4u* E5u* E6u* E7u* E8u*




Direct products of irreducible representations


Binary products
Ag Bg E1g* E2g* E3g* E4g* E5g* E6g* E7g* E8g* Au Bu E1u* E2u* E3u* E4u* E5u* E6u* E7u* E8u*
Ag Ag
Bg BgAg
E1g* E1gE8g2Ag⊕E2g
E2g* E2gE7gE1g⊕E3g2Ag⊕E4g
E3g* E3gE6gE2g⊕E4gE1g⊕E5g2Ag⊕E6g
E4g* E4gE5gE3g⊕E5gE2g⊕E6gE1g⊕E7g2Ag⊕E8g
E5g* E5gE4gE4g⊕E6gE3g⊕E7gE2g⊕E8g2Bg⊕E1g2Ag⊕E8g
E6g* E6gE3gE5g⊕E7gE4g⊕E8g2Bg⊕E3gE2g⊕E8gE1g⊕E7g2Ag⊕E6g
E7g* E7gE2gE6g⊕E8g2Bg⊕E5gE4g⊕E8gE3g⊕E7gE2g⊕E6gE1g⊕E5g2Ag⊕E4g
E8g* E8gE1g2Bg⊕E7gE6g⊕E8gE5g⊕E7gE4g⊕E6gE3g⊕E5gE2g⊕E4gE1g⊕E3g2Ag⊕E2g
Au AuBuE1uE2uE3uE4uE5uE6uE7uE8uAg
Bu BuAuE8uE7uE6uE5uE4uE3uE2uE1uBgAg
E1u* E1uE8u2Au⊕E2uE1u⊕E3uE2u⊕E4uE3u⊕E5uE4u⊕E6uE5u⊕E7uE6u⊕E8u2Bu⊕E7uE1gE8g2Ag⊕E2g
E2u* E2uE7uE1u⊕E3u2Au⊕E4uE1u⊕E5uE2u⊕E6uE3u⊕E7uE4u⊕E8u2Bu⊕E5uE6u⊕E8uE2gE7gE1g⊕E3g2Ag⊕E4g
E3u* E3uE6uE2u⊕E4uE1u⊕E5u2Au⊕E6uE1u⊕E7uE2u⊕E8u2Bu⊕E3uE4u⊕E8uE5u⊕E7uE3gE6gE2g⊕E4gE1g⊕E5g2Ag⊕E6g
E4u* E4uE5uE3u⊕E5uE2u⊕E6uE1u⊕E7u2Au⊕E8u2Bu⊕E1uE2u⊕E8uE3u⊕E7uE4u⊕E6uE4gE5gE3g⊕E5gE2g⊕E6gE1g⊕E7g2Ag⊕E8g
E5u* E5uE4uE4u⊕E6uE3u⊕E7uE2u⊕E8u2Bu⊕E1u2Au⊕E8uE1u⊕E7uE2u⊕E6uE3u⊕E5uE5gE4gE4g⊕E6gE3g⊕E7gE2g⊕E8g2Bg⊕E1g2Ag⊕E8g
E6u* E6uE3uE5u⊕E7uE4u⊕E8u2Bu⊕E3uE2u⊕E8uE1u⊕E7u2Au⊕E6uE1u⊕E5uE2u⊕E4uE6gE3gE5g⊕E7gE4g⊕E8g2Bg⊕E3gE2g⊕E8gE1g⊕E7g2Ag⊕E6g
E7u* E7uE2uE6u⊕E8u2Bu⊕E5uE4u⊕E8uE3u⊕E7uE2u⊕E6uE1u⊕E5u2Au⊕E4uE1u⊕E3uE7gE2gE6g⊕E8g2Bg⊕E5gE4g⊕E8gE3g⊕E7gE2g⊕E6gE1g⊕E5g2Ag⊕E4g
E8u* E8uE1u2Bu⊕E7uE6u⊕E8uE5u⊕E7uE4u⊕E6uE3u⊕E5uE2u⊕E4uE1u⊕E3u2Au⊕E2uE8gE1g2Bg⊕E7gE6g⊕E8gE5g⊕E7gE4g⊕E6gE3g⊕E5gE2g⊕E4gE1g⊕E3g2Ag⊕E2g

Ternary Products
Quaternary Products



Symmetric powers [Γn] of degenerate irreducible representations
Vibrational overtones


irrep 2] 3] 4] 5] 6]
E1g* Ag⊕E2gE1g⊕E3gAg⊕E2g⊕E4gE1g⊕E3g⊕E5gAg⊕E2g⊕E4g⊕E6gMore
E2g* Ag⊕E4gE2g⊕E6gAg⊕E4g⊕E8gE2g⊕E6g⊕E8gAg⊕E4g⊕E6g⊕E8gMore
E3g* Ag⊕E6g2Bg⊕E3gAg⊕2E6g2Bg⊕2E3g3Ag⊕2E6gMore
E4g* Ag⊕E8gE4g⊕E6gAg⊕E2g⊕E8gE2g⊕E4g⊕E6gAg⊕E2g⊕E6g⊕E8gMore
E5g* Ag⊕E8gE3g⊕E5gAg⊕E2g⊕E8gE3g⊕E5g⊕E7gAg⊕E2g⊕E6g⊕E8gMore
E6g* Ag⊕E6g2Ag⊕E6gAg⊕2E6g2Ag⊕2E6g3Ag⊕2E6gMore
E7g* Ag⊕E4gE3g⊕E7gAg⊕E4g⊕E8gE1g⊕E3g⊕E7gAg⊕E4g⊕E6g⊕E8gMore
E8g* Ag⊕E2gE6g⊕E8gAg⊕E2g⊕E4gE4g⊕E6g⊕E8gAg⊕E2g⊕E4g⊕E6gMore
E1u* Ag⊕E2gE1u⊕E3uAg⊕E2g⊕E4gE1u⊕E3u⊕E5uAg⊕E2g⊕E4g⊕E6gMore
E2u* Ag⊕E4gE2u⊕E6uAg⊕E4g⊕E8gE2u⊕E6u⊕E8uAg⊕E4g⊕E6g⊕E8gMore
E3u* Ag⊕E6g2Bu⊕E3uAg⊕2E6g2Bu⊕2E3u3Ag⊕2E6gMore
E4u* Ag⊕E8gE4u⊕E6uAg⊕E2g⊕E8gE2u⊕E4u⊕E6uAg⊕E2g⊕E6g⊕E8gMore
E5u* Ag⊕E8gE3u⊕E5uAg⊕E2g⊕E8gE3u⊕E5u⊕E7uAg⊕E2g⊕E6g⊕E8gMore
E6u* Ag⊕E6g2Au⊕E6uAg⊕2E6g2Au⊕2E6u3Ag⊕2E6gMore
E7u* Ag⊕E4gE3u⊕E7uAg⊕E4g⊕E8gE1u⊕E3u⊕E7uAg⊕E4g⊕E6g⊕E8gMore
E8u* Ag⊕E2gE6u⊕E8uAg⊕E2g⊕E4gE4u⊕E6u⊕E8uAg⊕E2g⊕E4g⊕E6gMore



Spherical harmonics and Multipoles
Symmetric Powers of Γxyz


Spherical Harmonics Yl / Multipole Symmetric Power [Γl(xyz)]
l 2l+1 Multipole Symmetry Rank l(xyz)]
s (l=0) 1 Monopole Ag 1 Ag
p (l=1) 3 Dipole Au⊕E1u 3 Au⊕E1u
d (l=2) 5 Quadrupole Ag⊕E1g⊕E2g 6 2Ag⊕E1g⊕E2g
f (l=3) 7 Octupole Au⊕E1u⊕E2u⊕E3u 10 2Au⊕2E1u⊕E2u⊕E3u
g (l=4) 9 Hexadecapole Ag⊕E1g⊕E2g⊕E3g⊕E4g 15 3Ag⊕2E1g⊕2E2g⊕E3g⊕E4g
h (l=5) 11 Dotricontapole Au⊕E1u⊕E2u⊕E3u⊕E4u⊕E5u 21 3Au⊕3E1u⊕2E2u⊕2E3u⊕E4u⊕E5u
i (l=6) 13 Tetrahexacontapole Ag⊕E1g⊕E2g⊕E3g⊕E4g⊕E5g⊕E6g 28 4Ag⊕3E1g⊕3E2g⊕2E3g⊕2E4g⊕E5g⊕E6g
j (l=7) 15 Octacosahectapole Au⊕E1u⊕E2u⊕E3u⊕E4u⊕E5u⊕E6u⊕E7u 36 4Au⊕4E1u⊕3E2u⊕3E3u⊕2E4u⊕2E5u⊕E6u⊕E7u
k (l=8) 17 256-pole Ag⊕E1g⊕E2g⊕E3g⊕E4g⊕E5g⊕E6g⊕E7g⊕E8g 45 5Ag⊕4E1g⊕4E2g⊕3E3g⊕3E4g⊕2E5g⊕2E6g⊕E7g⊕E8g
l (l=9) 19 512-pole Au⊕2Bu⊕E1u⊕E2u⊕E3u⊕E4u⊕E5u⊕E6u⊕E7u⊕E8u 55 5Au⊕2Bu⊕5E1u⊕4E2u⊕4E3u⊕3E4u⊕3E5u⊕2E6u⊕2E7u⊕E8u
m (l=10) 21 1024-pole Ag⊕2Bg⊕E1g⊕E2g⊕E3g⊕E4g⊕E5g⊕E6g⊕E7g⊕2E8g 66 6Ag⊕2Bg⊕5E1g⊕5E2g⊕4E3g⊕4E4g⊕3E5g⊕3E6g⊕2E7g⊕3E8g
n (l=11) 23 2048-pole Au⊕2Bu⊕E1u⊕E2u⊕E3u⊕E4u⊕E5u⊕E6u⊕2E7u⊕2E8u 78 6Au⊕4Bu⊕6E1u⊕5E2u⊕5E3u⊕4E4u⊕4E5u⊕3E6u⊕4E7u⊕3E8u
o (l=12) 25 4096-pole Ag⊕2Bg⊕E1g⊕E2g⊕E3g⊕E4g⊕E5g⊕2E6g⊕2E7g⊕2E8g 91 7Ag⊕4Bg⊕6E1g⊕6E2g⊕5E3g⊕5E4g⊕4E5g⊕5E6g⊕4E7g⊕5E8g
More

First nonvanshing multipole: Quadrupole

Further Reading

  • A. Gelessus, W. Thiel, W. Weber. J. Chem. Educ. 72 505 (1995)
    Multipoles and symmetry




Ligand Field, dn term splitting


Term symbols for electronic configurations dn
dn Term Symbols
d1 = d9 2D
d2 = d8 1S, 1D, 1G, 3P, 3F
d3 = d7 2P, 2D (2), 2F, 2G, 2H, 4P, 4F
d4 = d6 1S (2), 1D (2), 1F, 1G (2), 1I, 3P (2), 3D, 3F (2), 3G, 3H, 5D
d5 2S, 2P, 2D (3), 2F (2), 2G (2), 2H, 2I, 4P, 4D, 4F, 4G, 6S


Term splitting in point group C18h
L 2L+1 Term Splitting
S (L=0) 1 Ag
P (L=1) 3 Ag⊕E1g
D (L=2) 5 Ag⊕E1g⊕E2g
F (L=3) 7 Ag⊕E1g⊕E2g⊕E3g
G (L=4) 9 Ag⊕E1g⊕E2g⊕E3g⊕E4g
H (L=5) 11 Ag⊕E1g⊕E2g⊕E3g⊕E4g⊕E5g
I (L=6) 13 Ag⊕E1g⊕E2g⊕E3g⊕E4g⊕E5g⊕E6g


Last update November, 13th 2023 by A. Gelessus, Impressum, Datenschutzerklärung/DataPrivacyStatement