Second-order nonlinear optical properties of transition metal clusters [MoS4Cu4X2Py2] (M = Mo, W; X = Br, I)

Abstract

We present in this paper the second-order nonlinear optical properties of a series of penta-nuclear metal clusters [MS4Cu4X2Py6] (M=Mo, W; X=Br, I) on the basis of the hyper-Rayleigh scattering experiments and the first-principle calculations (TDDFT). The measurements obtain the notably large dynamic quadratic hyperpolarizabilities at 1064 nm [beta(-2omega, omega, omega) values are around 200x10(-30) esu] and, by extrapolation, a large static values around 60x10(-30) esu. The computational results of the electronic excitation energies and quadratic hyperpolarizabilities by TDDFT method are in good agreement with the experimental values and by careful examination they are both dependent on the nature of the metals. The in-depth analysis of the mechanism for the second-order response unambiguously shows the evidence of the contribution of direct metal-metal interaction charge transfers. This provides a new tool to tune nonlinear optical properties in exploiting metal cluster materials and molecular devices.

Cu(I) hybrid inorganic–organic materials with intriguing stimuli responsive and optoelectronic properties

“…developed a Cu(I) complex 127 with a bipy ligand, namely 4,4",6,6"-tetramethyl-2,2"-bipyridine, able to show reversible photochromic switching of NLO properties [150]. [151]. HLS measurements on bromide clusters resulted in β values equal to 164 x 10 -30 and 198 x 10 -30 esu for 128a, having a Mo central atom, and 128c, with a W atom, respectively.…”

Origin of the Enhancement of the Second Hyperpolarizabilities in Open-Shell Singlet Transition-Metal Systems with Metal–Metal Multiple Bonds

“…Therefore, transition-metal complexes with multiple metalÀ metal bonds also appear as promising systems for their thirdorder NLO properties, which constitutes the topic of this Letter, where the γ values of two kinds of open-shell singlet metalÀ metal bonded systems are investigated to clarify the origin of γ from the viewpoint of the multiple diradical characters of dσ, dπ, and dδ orbitals. The direct metalÀmetal bond contributions to the NLO properties have not been investigated, except in a few theoretical and experimental studies on, for example, the (hyper)polarizabilities of the copper dimer 12 and the first hyperpolarizabilities (β) of dirhenium complexes 13 and pentanuclear transition metal clusters, 14 The Journal of Physical Chemistry Letters LETTER dÀorbital overlaps, each of the dσ, dπ, and dδ orbitals displays a different diradical character for a given bond length.…”

Resonant-Convergent PCM Response Theory for the Calculation of Second Harmonic Generation in Makaluvamines A–V: Pyrroloiminoquinone Marine Natural Products from Poriferans of Genus Zyzzya

“…The results of the static hyperpolarizability calculations are given in Table . The values presented correspond to the orientationally averaged first hyperpolarizability in accordance with …”