Last updated
IUPAC name
Other names
8-Hydroxyquinoline aluminium salt, Alq3, aluminium 8-hydroxyquinolinate, aluminium oxinate,
3D model (JSmol)
ECHA InfoCard 100.016.570 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 218-227-0
PubChem CID
  • InChI=1S/3C9H7NO.Al.9H/c3*11-8-5-1-3-7-4-2-6-10-9(7)8;;;;;;;;;;/h3*1-6,11H;;;;;;;;;;/p-3 Yes check.svgY
  • InChI=1/3C9H7NO.Al.9H/c3*11-8-5-1-3-7-4-2-6-10-9(7)8;;;;;;;;;;/h3*1-6,11H;;;;;;;;;;/p-3/rC27H27AlN3O3/c1-7-19-10-4-16-29-25(19)22(13-1)32-28(29,30-17-5-11-20-8-2-14-23(33-28)26(20)30)31-18-6-12-21-9-3-15-24(34-28)27(21)31/h1-18H,28H9/q-3
  • c7ccc8cccc9O[AlH3-6]36(Oc2cccc1ccc[n+]3c12)(Oc5cccc4ccc[n+]6c45)[n+]7c89
Molar mass 459.43
AppearanceYellow powder
Melting point > 300 °C (572 °F; 573 K)
insoluble in water
GHS pictograms GHS-pictogram-exclam.svg
GHS Signal word Warning
H315, H319, H335
P261, P264, P271, P280, P302+352, P304+340, P305+351+338, P312, P321, P332+313, P337+313, P362, P403+233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Tris(8-hydroxyquinolinato)aluminium is the chemical compound with the formula Al(C9H6NO)3. Widely abbreviated Alq3, it is a coordination complex wherein aluminium is bonded in a bidentate manner to the conjugate base of three 8-hydroxyquinoline ligands.



Both the meridional and facial isomers are known as well as several polymorphs (different crystalline forms). [1]

Mer-tris(8-hydroxyquinoline)aluminium(III)-from-xtal-2000-CM-3D-ellipsoids.png Fac-tris(8-hydroxyquinoline)aluminium(III)-from-xtal-2003-CM-3D-ellipsoids.png
Thermal ellipsoid model of mer-Alq3 [2] Thermal ellipsoid model of fac-Alq3 [3]


The compound is prepared by the reaction of 8-hydroxyquinoline with aluminium(III) sources [4]

Al3+ + 3 C9H7NO → Al(C9H6NO)3 + 3 H+


Alq3 is a common component of organic light-emitting diodes (OLEDs). Variations in the substituents on the quinoline rings affect its luminescence properties. [5]

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  1. Cölle, M.; Dinnebier, R. E.; Brütting, W. (2002). "The structure of the blue luminescent δ-phase of tris(8-hydroxyquinoline)aluminium(III) (Alq3)". Chemical Communications. 2002 (23): 2908–9. doi:10.1039/b209164j. PMID   12478807.
  2. Brinkmann, M.; Gadret, G.; Muccini, M.; Taliani, C.; Masciocchi, N.; Sironi, A. (2000). "Correlation between Molecular Packing and Optical Properties in Different Crystalline Polymorphs and Amorphous Thin Films of mer-Tris(8-hydroxyquinoline)aluminum(III)". J. Am. Chem. Soc. 122 (21): 5147–57. doi:10.1021/ja993608k.
  3. Rajeswaran, M.; Blanton, T. N.; Klubek, K. P. (2003). "Refinement of the crystal structure of the δ-modification of tris(8-hydroxyquinoline)aluminum(III), δ-Al(C9H6NO)3, the blue luminescent Alq3". Zeitschrift für Kristallographie – New Crystal Structures. 218 (4): 439–40. doi: 10.1524/ncrs.2003.218.jg.471 .
  4. Katakura, R.; Koide, Y. (2006). "Configuration-Specific Synthesis of the Facial and Meridional Isomers of Tris(8-hydroxyquinolinate)aluminum (Alq3)". Inorg. Chem. 45 (15): 5730–2. doi:10.1021/ic060594s. PMID   16841973.
  5. Montes, V. A.; Pohl, R.; Shinar, J.; Anzenbacher, P. Jr. (2006). "Effective Manipulation of the Electronic Effects and Its Influence on the Emission of 5-Substituted Tris(8-quinolinolate) Aluminum(III) Complexes". Chemistry: A European Journal. 12 (17): 4523–35. doi:10.1002/chem.200501403. PMID   16619313.