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We report the synthesis and characterization of (Ph4P)2SbCl5, a novel ionically bonded organic metal halide hybrid with a zero-dimensional (0D) structure at the molecular level. By cocrystallization of tetraphenylphosphonium (Ph4P+) and antimony (Sb3+) chloride salts, (Ph4P)2SbCl5 bulk single crystals can be prepared in high yield, which exhibit a highly efficient broadband red emission peaked at 648 nm with a photoluminescence quantum efficiency (PLQE) of around 87%. Density functional theory (DFT) calculations reveal the origin of emission as phosphorescence from the excitons localized at SbCl52- with strong excited-state structural distortion. Interestingly, (Ph4P)2SbCl5 bulk crystals with a PLQE of around 100% can be prepared via a rapid crystal growth process within minutes, followed by a spontaneous structural transformation. It was found that the rapid growth process yielded a yellow emitting kinetically favored metastable product containing solvent molecules, which turned into the red emitting thermodynamically stable product slowly at room temperature or quickly upon thermal treatment. [ABSTRACT FROM AUTHOR]

Three bis-tetradentate acyclic amine ligands differing only in the arm length of the pyridine pendant arms attached to the 4,6-positions of the pyrimidine ring, namely, 4,6-bis[N,N-bis(2'-pyridylethyl)aminomethyl]-2-phenylpyri-midine (LEt),4,6-bis[N,N-bis(2'-pyridymiethyl)aminomethyl]-2-phenylpyrimidine(LMe), and 4,6-[(2'-pyridyImethyl)-2'-pyridylethyl)ammomethyl]-2-phenylpyrimidine(LMix) have been used to synthesize nine air-sensitive diiron(II) complexes: [FeII2LEt(NCS)4]-MeOH-3/4H2O(l-MeOH-3/4H2O),[FeII2LEt(NCSe)4]-H2O(2-H2O),[FeII,LEt(NCBH3)4]-5/2H2O(3-5/2H2O),[FeII2LMe(NCS)4-½>/H2.O (4-½>H2O),[FeII2LMeCNCSe)4] (5), [FeII2LMe(NCBH3)4]-3/2H2O (6-3/2H2O), [FeII2LMix(NCS)4]-½>H2O (7-½>H2O), [FeII2LMix(NCSe)4]-3/22H2O (8-3/2H2O), and [FeII2LMix(NCBH3)4]-3/2H2O (9-3/2H2O). Complexes 3-5/2H2O, 4-'/2H2O, 5, 6-3/2H2O, and 8-3/2H2O were structurally characterized by X-ray crystallography, revealing, in all cases, both of the iron(II) centers in an octahedral environment with two NCE (E = S, Se, or BH3) anions in a cis-position relative to one another. Variable temperature magnetic susceptibility measurements showed that all nine diiron(II) complexes are stabilized in the [HS-HS] state from 300 K to 4 K, and exhibit weak antiferromagnetic coupling. Mossbauer spectroscopy confirmed the spin and oxidation states of eight of the nine complexes (the synthesis of air-sensitive complex 3 was not readily reproduced). [ABSTRACT FROM AUTHOR]

Three bis-tetradentate acyclic amine ligands differing only in the arm length of the pyridine pendant arms attached to the 4,6-positions of the pyrimidine ring, namely, 4,6-bis[N,N-bis(2'-pyridylethyl)aminomethyl]-2-phenylpyrimidine (L(Et)), 4,6-bis[N,N-bis(2'-pyridylmethyl)aminomethyl]-2-phenylpyrimidine (L(Me)), and 4,6-[(2'-pyridylmethyl)-2'-pyridylethyl)aminomethyl]-2-phenylpyrimidine (L(Mix)) have been used to synthesize nine air-sensitive diiron(II) complexes: [Fe(II)(2)L(Et)(NCS)(4)]·MeOH·¾H(2)O (1·MeOH·¾H(2)O), [Fe(II)(2)L(Et)(NCSe)(4)]·H(2)O (2·H(2)O), [Fe(II)(2)L(Et)(NCBH(3))(4)]·(5/2)H(2)O (3·(5/2)H(2)O), [Fe(II)(2)L(Me)(NCS)(4)]·½H(2)O (4·½H(2)O), [Fe(II)(2)L(Me)(NCSe)(4)] (5), [Fe(II)(2)L(Me)(NCBH(3))(4)]·(3/2)H(2)O (6·(3/2)H(2)O), [Fe(II)(2)L(Mix)(NCS)(4)]·½H(2)O (7·½H(2)O), [Fe(II)(2)L(Mix)(NCSe)(4)]·(3/2)H(2)O (8·(3/2)H(2)O), and [Fe(II)(2)L(Mix)(NCBH(3))(4)]·(3/2)H(2)O (9·(3/2)H(2)O). Complexes 3·(5/2)H(2)O, 4·½H(2)O, 5, 6·(3/2)H(2)O, and 8·(3/2)H(2)O were structurally characterized by X-ray crystallography, revealing, in all cases, both of the iron(II) centers in an octahedral environment with two NCE (E = S, Se, or BH(3)) anions in a cis-position relative to one another. Variable temperature magnetic susceptibility measurements showed that all nine diiron(II) complexes are stabilized in the [HS-HS] state from 300 K to 4 K, and exhibit weak antiferromagnetic coupling. Mössbauer spectroscopy confirmed the spin and oxidation states of eight of the nine complexes (the synthesis of air-sensitive complex 3 was not readily reproduced).