英语翻译It should be noted that although shifts in the 1H NMRspectrum of 3 in CD3CN provide evidence of p-stacking athigh concentrations (1 to 11 mM,Fig.S3,ESIw),similar torelated systems,12 these interactions are negligible at concentrationsr0.5
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英语翻译It should be noted that although shifts in the 1H NMRspectrum of 3 in CD3CN provide evidence of p-stacking athigh concentrations (1 to 11 mM,Fig.S3,ESIw),similar torelated systems,12 these interactions are negligible at concentrationsr0.5
英语翻译
It should be noted that although shifts in the 1H NMR
spectrum of 3 in CD3CN provide evidence of p-stacking at
high concentrations (1 to 11 mM,Fig.S3,ESIw),similar to
related systems,12 these interactions are negligible at concentrations
r0.5 mM in this solvent.The absorption and luminescence
spectra of 3 were collected at concentrations well below
this value (5–70 mM),such that the photophysical data are
expected to correspond to monomeric 3 in solution.
The transient absorption spectra of 3 collected in the ns to
ms timescale are similar to that previously reported for the
complex and to that of the free dppn ligand,featuring a strong
absorption band at 540 nm with t = 33 \3 5 ms in CH3CN
(Fig.S4,ESIw).9b A lifetime of 18 \3 2 ms was measured
for free dppn in CHCl3,typical of 3pp* excited states of
polycyclic aromatic heterocycles.13 As previously discussed,9b
the lowest-energy excited state of 3 is therefore assignedas dppn-localized 3pp*.In contrast,2 is well known to exhibit
3MLCT as the lowest excited state (t = 750 ns) in CH3CN.14
Ultrafast transient absorption spectra were collected to
ascertain the presence of an emissive 3MLCT state and nonemissive
3pp* in the same complex.Although not
unprecedented,8,9 such behavior is unusual.The signal at
370 nm is known to be associated with the 3MLCT state,
and its intensity remains relatively constant from 1 to 20 ps
(Fig.2a).The 3pp* absorption at 536 nm grows at early times
with a risetime of 2.1(4) ps,then remains unchanged from
20 ps to 2 ns (Fig.2).Some contribution from the broad
3MLCT absorption in the 500–650 nm range is also expected,
similar to that of 2 (Fig.S5,ESIw).Since the 3MLCT signal
does not decrease while that of the 3pp* state increases at early
times (Fig.2a),it may be concluded that the latter is not
populated from the former.Therefore,it is believed that
intersystem crossing (isc) results in population of both the
3MLCT and 3pp*,as previously described for related
systems.15,16 A slight decrease in the 3MLCT signal is observed
from 20 ps to 1 ns,which can be associated with the decay of
that state and is also observed for 2 (Fig.S5,ESIw).
英语翻译It should be noted that although shifts in the 1H NMRspectrum of 3 in CD3CN provide evidence of p-stacking athigh concentrations (1 to 11 mM,Fig.S3,ESIw),similar torelated systems,12 these interactions are negligible at concentrationsr0.5
应该指出,虽然3在CD3CN中的1H 核磁共振谱的漂移提供了在高浓度(1到11mM,图S3,ESI)下π堆积的证据,与有关的系统相似12,这些互作用在这种溶剂中浓度≤0.5mM时可忽略不计.3的的吸收和发光谱是在在明显低于此值(5-70μM)的浓度下采集的,这样,光物理数据预计相应于溶液中的单体3.
在ns到μs时间量度中采集的3的瞬态吸收谱类似于以前对该络合物报道的瞬态吸收谱,并类似于游离dppn配体的瞬态吸收谱,体现了在CH3CN中τ=33±5μs时于540nm处强吸收带的特点(图S4,ESI)9b.对于CHCl3中的游离dppn,测得了18±2μs的寿命时间,这是多环芳香杂环的3ππ*激发态典型的13.如以前讨论的那样9b,3的最低能级激发态因此被指定为dppn局限的3ππ*.与此相反,众所周知2在CH3CN中显示3MLCT作为最低激发态(τ=750ns)14.
我们采集了超快瞬态吸收谱,以确定同一络合物中发射3MLCT态和非发射3ππ*态的存在.虽然不是没有先例的8,9,但这一性状是不寻常的.在370nm处的信号已知与3MLCT态相关,其强度从1到20ps保持相对恒定(图2a).在536nm处的3ππ*吸收在早期随着2.1(4)ps的上升时间增长,然后从20ps到2ns保持不变(图2).来自500-650nm范围宽的3MLCT吸收的某些贡献也是预料之中的,这与2的情况类似(图S5,ESI).由于3MLCT信号不下降,而3ππ*态的吸收在早期增加(图2a),所以可以得出结论,后者没有被前者充满(populated).因此,人们相信,系统间的交叉(isc)导致了3MLCT和3ππ*两种态的群体,就像前面对有关系统描述的那样15,16.从20ps到1ns观察到了3MLCT信号的少许下降,这可以与该态的衰落相关联,而且对2也观察到了(图S5,ESI).
值得注意的是,虽然制氢谱
3在CD3CN谱的p-stacking提供依据
高浓度(1 ~ 11毫米,图。轻度、ESIw),类似
12这些交互作用与制度,是可以忽略不计的浓度
在这r0.5毫米。吸收和发光
3在光谱浓度低于
这个值(5-70毫米),这样的光物理数据
预计在溶液中相对应的monomeric 3。
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值得注意的是,虽然制氢谱
3在CD3CN谱的p-stacking提供依据
高浓度(1 ~ 11毫米,图。轻度、ESIw),类似
12这些交互作用与制度,是可以忽略不计的浓度
在这r0.5毫米。吸收和发光
3在光谱浓度低于
这个值(5-70毫米),这样的光物理数据
预计在溶液中相对应的monomeric 3。
瞬态吸收光谱特性,在ns 3收藏
时间就像微软先前报道
复杂的自由dppn配体,具有强烈的
吸收乐队在540海里与t = 33岁的女士在CH3CN 5
(图。第四,ESIw).9b一辈子的18岁的女士是2
在CHCl3 dppn免费,典型的3pp *激发态的
像先前讨论了多heterocycles.13,由王昭平
这个lowest-energy兴奋状态,因此assignedas dppn-localized三3pp *。相反,二是广为人知的展览
3MLCT最低的兴奋状态(如在t = CH3CN.14 750 ns)
快速瞬时吸收光谱是收藏
确定的存在状态,nonemissive 3MLCT放射性
3pp *在相同的复杂。虽然不是
前所未有的、8、9这样的行为是不寻常的。这个信号
370海里的功能是在3MLCT状态,
和它的强度相对保持1 ~ 20注
(图2)。这个3pp *吸收在536海里生长在早期的时候
有risetime为2.1(4)ps,然后维持不变
20 ps 2 ns”(图2)。从广义的一些贡献
3MLCT吸收的500-650纳米预计也,
类似于2(图。ESIw S5、)。自从3MLCT信号
没有减少,而这个3pp *国家增加在早期的吗
(图2次),它可能得出的结论是,后者则不是
从以前的人口。因此,人们相信
intersystem isc(在交叉的人口
3MLCT和3pp *,如前所描述为相关
systems.15略有下降,16岁的3MLCT信号
从20 ps 1坏死性涎腺化生,可以联系在一起的
那个国家,也观察到2(图。ESIw S5、)。
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应当指出,虽然变化的核磁共振
3谱CD3CN提供的P -堆放在证据
高浓度(1到11毫米,图。中三,ESIw),类似于
相关系统,12这些相互作用可以忽略不计的浓度
r0.5 mM的这一溶剂。吸收与发光
3光谱进行收集浓度远低于
此值(5A条€“70毫米),这样的光物理数据
预计对应于解决单体3。
在3瞬态吸收光谱中所采集的NS
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应当指出,虽然变化的核磁共振
3谱CD3CN提供的P -堆放在证据
高浓度(1到11毫米,图。中三,ESIw),类似于
相关系统,12这些相互作用可以忽略不计的浓度
r0.5 mM的这一溶剂。吸收与发光
3光谱进行收集浓度远低于
此值(5A条€“70毫米),这样的光物理数据
预计对应于解决单体3。
在3瞬态吸收光谱中所采集的NS
毫秒时间尺度是类似于以前的报告
复杂和自由dppn配体的,具有强大的
吸收带在540吨纳米= 33 5乙腈毫秒
(图中四,ESIw)0.9 B只需18 2毫秒寿命测量
免费dppn在氯仿,典型3pp的*激发态
多环芳烃heterocycles.13如前所述,第9b
最低能量激发态的3因此assignedas dppn本地化3pp的*.相比之下,二是众所周知的展览
三毫升
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