英语翻译Photophysical Properties and pH Dependence.The electroni

英语翻译
Photophysical Properties and pH Dependence.The electronic
absorption maxima,molar extinction coefficients,
and emission properties of 1-3 are listed in Table 1.The
absorption,excitation,and emission spectra of 3 at room
temperature inwater and at 77KinMeOH/EtOH(1:4,v/v)
are plotted in Figure 2.Complex 3 exhibits the typical
singlet metal-to-ligand charge-transfer (1MLCT) absorption
band of ruthenium polypyridyl complexes with a
maximum at 457 nm and a shoulder at∼430 nm (Figure 2
and Table 1).11 In the ultraviolet region,its absorption is
dominated by the intense ligand-centered (LC) ππ* transition
from the ancillary bpy ligands with a maximum at
287 nm.11 A peak at 365 nm is attributed to the dpqpbased
LC transition,a feature similar to those of 2 at 359
and 370 nm.However,unlike 2,which is not emissive in
water,3 exhibits strong luminescence (Φem=0.039) with a
maximum at 617 nm that can be fitted to a monoexponential
decay with τ=582 ns (λexc=355 nm,fwhm ∼8 ns,
under argon; Figure 2).These values are comparable to
those of 1 in water (Φem=0.042,λem=626 nm,τ=630 ns).
The excitation spectrum of 3 monitored at 617 nm overlays
well with its ground state absorption spectrum in
water,indicating that the strong luminescence arises from
3 and not from a highly emissive impurity.As shown in
Figure 2,the 77 K emission spectrum of 3 displays a
vibronic structure with maxima at 576 and 625 nm (Δν ≈ 1361 cm-1) that is typical of the 3MLCT luminescence
of ruthenium polypyridyl complexes,including 1 (582
and 629 nm; Δν ≈ 1284 cm-1) and 2 (582 and 630 nm;
Δν ≈ 1309 cm-1) under similar experimental conditions
(Table 1).11

光物理性质和pH相关性.络合物1－3的电子吸收最大值、克分子消光系数和发射性质列于表1.3在室温水中,以及在MeOH/EtOH (1:4,v/v)中77K下的吸收、激发和发射谱绘于图2.络合物3呈现出钌多吡啶典型的单重金属与配体的电荷传递（1MLCT）吸收带,最大值在457nm处,430nm处则是一个肩部（图2和表1）11.在紫外区,其吸收受来自于附属bpy配体的,最大值在287nm处的,集中的以配体为中心（LC）的ππ*跃迁所主导11.在365nm处的峰值归因于dpqp基的LC跃迁,这是类似于络合物2在359和370nm处峰值的特点.然而,和2不同,3在水中是不发射的,它呈现出最大值的617nm处的强烈发光（Φem=0.039),这可以拟合成τ＝582ns的单指数式衰减（λexc＝355nm,fwhm~8ns,在氩气下；图2）.这些值与络合物1在水中的值相当（Φem=0.042,λem=626nm,τ＝630ns).3在617nm出监测到的激发谱与其在水中的基态吸收谱重叠良好,表明了从3发生了强烈的发光,而不是来自于高发射的杂质.如图2所示的那样,3在77K时的发射谱显示了最大值在576nm和625nm处的振动结构（Δv≈1361cm－1）,这是包括1（582和629nm；Δv≈1284cm－1）和2（582和630nm；Δv≈1309cm－1）的钌多吡啶络合物在类似的试验条件下的3MLCT发光典型的（表1）11.