TY - JOUR
T1 - Organometallic complexes for nonlinear optics Part 21. Syntheses and quadratic hyperpolarizabilities of alkynyl complexes containing optically active 1,2-bis(methylphenylphosphino)benzene ligands
AU - McDonagh, Andrew M.
AU - Cifuentes, Marie P.
AU - Humphrey, Mark G.
AU - Houbrechts, Stephan
AU - Maes, Joachim
AU - Persoons, André
AU - Samoc, Marek
AU - Luther-Davies, Barry
PY - 2000/9/22
Y1 - 2000/9/22
N2 - The preparation of the chloro complex trans-[FeCl2{(R,R)-diph}2] (1) and the alkynyl complexes trans-[M(4-C≡CC6H4R)Cl{(R,R)-diph}2] [M = Fe, R = NO2 (2); M = Ru, R = H (4), NO2 (5), (E)-CH=CH-4-C6H4NO2 (6); M = Os, R = NO2 (7)], incorporating the optically active diphosphine 1,2-bis(methylphenylphosphino)benzene (diph), are described. Oxidation potentials, as determined by cyclic voltammetry, increase as 2 < 7 < 5. Molecular quadratic nonlinearities by hyper-Rayleigh scattering at 1064 nm increase upon introduction of an acceptor group (4 < 5), chain-lengthening of bridging group (5 < 6), and proceeding from 3d to 4d and 5d metal (2 ≤ 5 ≤ 7). Two-level-corrected nonlinearities reproduce the first two trends, but metal variation follows the sequence 2 < 7 < 5. The experimental and two-level-corrected nonlinearities for 6 (2795 × 10-30 and 406 × 10-30 esu, respectively), are amongst the largest observed thus far for organometallic complexes. Crystals of complexes 2 and 7 exhibit second-harmonic generation (assessed using the Kurtz powder technique), with an efficiency for the former of twice that of urea.
AB - The preparation of the chloro complex trans-[FeCl2{(R,R)-diph}2] (1) and the alkynyl complexes trans-[M(4-C≡CC6H4R)Cl{(R,R)-diph}2] [M = Fe, R = NO2 (2); M = Ru, R = H (4), NO2 (5), (E)-CH=CH-4-C6H4NO2 (6); M = Os, R = NO2 (7)], incorporating the optically active diphosphine 1,2-bis(methylphenylphosphino)benzene (diph), are described. Oxidation potentials, as determined by cyclic voltammetry, increase as 2 < 7 < 5. Molecular quadratic nonlinearities by hyper-Rayleigh scattering at 1064 nm increase upon introduction of an acceptor group (4 < 5), chain-lengthening of bridging group (5 < 6), and proceeding from 3d to 4d and 5d metal (2 ≤ 5 ≤ 7). Two-level-corrected nonlinearities reproduce the first two trends, but metal variation follows the sequence 2 < 7 < 5. The experimental and two-level-corrected nonlinearities for 6 (2795 × 10-30 and 406 × 10-30 esu, respectively), are amongst the largest observed thus far for organometallic complexes. Crystals of complexes 2 and 7 exhibit second-harmonic generation (assessed using the Kurtz powder technique), with an efficiency for the former of twice that of urea.
KW - Alkynyl
KW - Chiral diphosphine
KW - Cyclic voltammetry
KW - Iron
KW - Nonlinear optics
KW - Osmium
KW - Quadratic hyperpolarizabilities
KW - Ruthenium
UR - http://www.scopus.com/inward/record.url?scp=0002002451&partnerID=8YFLogxK
U2 - 10.1016/S0022-328X(00)00420-4
DO - 10.1016/S0022-328X(00)00420-4
M3 - Article
SN - 0022-328X
VL - 610
SP - 71
EP - 79
JO - Journal of Organometallic Chemistry
JF - Journal of Organometallic Chemistry
IS - 1-2
ER -