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Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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II.A.1. (XV.A.)

Listing of experimental data for Al2Cl6 (Aluminum, di-μ-chlorotetrachlorodi-)

Other names
Aluminum chloride; Aluminum chloride, dimer; dialuminum hexachloride;
InChI=1S/2Al.4ClH.2Cl/h;;4*1H;;/q2*+2;;;;;;/p-4 GHSXCATXXREJIA-UHFFFAOYSA-J Cl[Al]1(Cl)Cl[Al](Cl)(Cl)Cl1
State Conformation
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Hfg(298.15K) enthalpy of formation -1295.74   kJ mol-1 webbook
Hfg(0K) enthalpy of formation     kJ mol-1 webbook
Entropy (298.15K) entropy 474.96   J K-1 mol-1 webbook
Heat Capacity (298.15K) heat capacity 158.40   J K-1 mol-1 webbook
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment

Calculated vibrational frequencies for Al2Cl6 (Aluminum, di-μ-chlorotetrachlorodi-).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment

Calculated rotational constants for Al2Cl6 (Aluminum, di-μ-chlorotetrachlorodi-).

Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6
Geometric Data
picture of Aluminum, di-μ-chlorotetrachlorodi-

Point Group D2h

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees

Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rAlCl 2.040 0.040 1 3 1976Hellwege(II/7) ED
rAlCl 2.240 0.040 1 5 1976Hellwege(II/7)
aClAlCl 122 6 5 1 6 1976Hellwege(II/7)
aClAlCl 87 6 3 1 4


Atom x (Å) y (Å) z (Å)
Al1 1.6248 0.0000 0.0000
Al2 -1.6248 0.0000 0.0000
Cl3 0.0000 0.0000 1.5419
Cl4 0.0000 0.0000 -1.5419
Cl5 2.6138 1.7842 0.0000
Cl6 2.6138 -1.7842 0.0000
Cl7 -2.6138 1.7842 0.0000
Cl8 -2.6138 -1.7842 0.0000

Atom - Atom Distances bond lengths
Distances in Å

  Al1 Al2 Cl3 Cl4 Cl5 Cl6 Cl7 Cl8
Al1   3.24962.24002.24002.04002.04004.59884.5988
Al2 3.2496   2.24002.24004.59884.59882.04002.0400
Cl3 2.24002.2400   3.08383.52043.52043.52043.5204
Cl4 2.24002.24003.0838   3.52043.52043.52043.5204
Cl5 2.04004.59883.52043.5204   3.56845.22766.3294
Cl6 2.04004.59883.52043.52043.5684   6.32945.2276
Cl7 4.59882.04003.52043.52045.22766.3294   3.5684
Cl8 4.59882.04003.52043.52046.32945.22763.5684  

Calculated geometries for Al2Cl6 (Aluminum, di-μ-chlorotetrachlorodi-).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
Al1 Cl3 Al2 92.999 Al1 Cl4 Al2 92.999
Cl3 Al1 Cl4 87.001 Cl3 Al1 Cl5 110.589
Cl3 Al1 Cl6 110.589 Cl3 Al2 Cl4 87.001
Cl3 Al2 Cl7 110.589 Cl3 Al2 Cl8 110.589
Cl4 Al1 Cl5 110.589 Cl4 Al1 Cl6 110.589
Cl4 Al2 Cl7 110.589 Cl4 Al2 Cl8 110.589
Cl5 Al1 Cl6 122.000 Cl7 Al2 Cl8 122.000

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
Al-Cl 8


Atom 1 Atom 2
Al1 Cl3
Al1 Cl4
Al1 Cl5
Al1 Cl6
Al2 Cl3
Al2 Cl4
Al2 Cl7
Al2 Cl8
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
For a molecule with D2h symmetry there is no dipole.
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for Al2Cl6 (Aluminum, di-μ-chlorotetrachlorodi-).

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squib reference DOI
1976Hellwege(II/7) Hellwege, KH and AM Hellwege (ed.). Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 7: Structure Data of Free Polyatomic Molecules. Springer-Verlag. Berlin. 1976.  
webbook NIST Chemistry Webbook (  

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