TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: The first organic layer is an emissive layer and (I) is a host in the first organic layer, where the emissive layer further comprises a phosphorescent emitter. The phosphorescent emitter is an iridium complex of formula (a1) or a compound comprising a phosphorescent metal complex comprising a monoanionic, bidentate ligand of formula (a2), where the metal is a non-radioactive metals with atomic numbers greater than 40 and the bidentate ligand may be linked with other ligands to comprise a tridentate, tetradentate, pentadentate or hexadentate ligand. The first organic layer is adjacent to the second organic layer. The phosphorescent emitter has a triplet energy of 425-495 (preferably 440-480) nm or 495-570 (preferably 510-530) nm. (I) is present at 10-100 (preferably 40-99.9) wt.%. The first electrode is an anode and the second electrode is a cathode. The device further comprises: a second organic layer that is a non-emissive layer and a phosphorescent emitter having a concentration of 0.1-30 wt.%. Preferred Method: In the method, an organic layer is deposited after the first electrode and before the emissive layer, where the organic layer is a hole transport layer.n = 1-3; eitherR1a-R1i = H, hydrocarbyl, heteroatom substituted hydrocarbyl, CN, fluoro, OR2a, SR2a, NR2aR2b, BR2aR2b or SiR2aR2bR2c; andR2a-R2c = hydrocarbyl or heteroatom substituted hydrocarbyl; orany two of R1a-R1i and R2a-R2c together = form aromatic or non-aromatic ring (optionally saturated);X-Y1 = ancillary ligand; andE1a-E1q = C or N and collectively comprise an 18 pi-electron system.Provided that: E1a and E1p are different; and R1a-R1i is other than H when attached to N.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation: No preparation method is given. Preferred Definitions:    a = 1;    b = 1;    n = 0 or 1;    X = dibenzothiophene, dibenzofuran, benzofuropyridine, furodipyridine, benzothienopyridine, 9H-carbazole, thienodipyridine or triphenylene (all preferred), biphenyl, terphenyl, phenanthrene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, triazine, benzimidazole, benzothiazole, quinoline or isoquinoline; and    R = H, alkyl, benzene, biphenyl, terphenyl, dibenzothiophene or dibenzofuran (all preferred), 2-phenyl-triphenylene, 2-triphenylen-2-yl-pyridine, benzo(4,5)furo(3,2-b)pyridine, furo(2,3-b, 5,4-b')dipyridine, benzo(4,5)thieno(2,3-b)pyridine, thieno(2,3-b, 5,4-b')dipyridine, triphenylene, phenanthrene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, triazine, benzimidazole, benzothiazole, quinoline, isoquinoline, benzofuropyridine, furodipyridine, benzothienopyridine or thienodipyridine.    SPECIFIC COMPOUNDS - 8 Compounds (I) are disclosed e.g. 9-pyridin-2-yl-9H-(3,9')bicarbazolyl of formula (Ia), 9-dibenzothiophen-4-yl-9H-(4,9')bicarbazolyl, 9-dibenzothiophen-2-yl-9H-(4,9')bicarbazolyl, 9-dibenzothiophen-2-yl-9H-(3,9';4',9'')tercarbazole and 9-dibenzofuran-2-yl-9H-(3,9')bicarbazolyl.    EXAMPLE - 3-Iodo-9-tosylcarbazole (10.6 g), carbazole (4.8 g), copper iodide (0.4 g), trans-1,2-diaminocyclohexane (0.3 g), tribasic potassium phosphate (10.6 g), and toluene (150 ml) were added to a flask. The reaction was heated to reflux, and worked up to give 3-(9-carbazolyl)-9-tosylcarbazole (10 g). 3-(9-Carbazolyl)-9-tosylcarbazole (10 g), sodium hydroxide (8 g), tetrahydrofuran (80 ml), methanol (40 ml) and water (40 ml) were added to a flask. The reaction was heated to reflux for 12 hours and worked up to give 3-(9-carbazolyl)carbazole (8 g). 3-(9-Carbazolyl)carbazole (3 g), 2-bromopyridine (1.9 g), copper iodide (0.2 g), trans-1,2-diaminocyclohexane (0.2 g), tribasic potassium phosphate (5.3 g), and toluene (150 ml) were added to a flask. The reaction was heated to reflux and worked up to give 9-pyridin-2-yl-9H-(3,9')bicarbazolyl (2.2 g).