silver tetramer

• 分子结构分类: 无机化合物 - 均相金属化合物 - 均相过渡金属化合物
• 英文名称: silver tetramer
• 英文别名: silver
• 化学式: Ag₄
• 分子量: 431.473
• InChiKey: FTHXNDRIJXQDTA-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -0.01
• 重原子数：
  4
• 可旋转键数：
  0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为产物：
  描述：

  [Ag4(pyridine)2]n 以 neat (no solvent) 为溶剂， 生成 silver tetramer
  参考文献：
  名称：

  楼梯状的分子银（0）链。

  摘要：

  DOI：

  10.1002/anie.200803465

文献信息

• Reactions of AgI ions in alcohols after radiolysis at 77 K
  作者：Robert Janes、Andrew D. Stevens、Martyn C. R. Symons

  DOI：10.1039/f19898503973

  日期：——

  Solutions of silver perchlorate in methanol, ethanol, ethane-1,2-diol, isopropyl alcohol, allyl and propargyl alcohols have been exposed to 60Co γ-rays at 77 K and the resulting radicals studied using ESR spectroscopy. In addition to ĊH2OH solvent radicals, methanolic solutions gave AgII centres and a number of discrete Ag° species. The latter exhibited a range of hyperfine couplings, reflecting various degrees of solvation. Their relative yields were shown to vary according to initial AgI concentration and with added sodium perchlorate. After annealing to ca. 120 K, Ag° gave way to the molecular cluster cations Ag+2, Ag2+3, Ag3+4 and Ag4+5, previously identified by ESR and optical spectroscopy in a range of systems and shown to be formed by the sequential addition of AgI ions. Ag4+5 formation was favoured either by high initial AgI or high counterion (nitrate or perchlorate) concentration. During the silver aggregation process the solvent radicals (CH2OH) decayed and the adduct [Ag . CH2OH]+ was formed [Aiso(Ag)= 128 G]. On annealing to the softening point of the matrix these species were lost. No higher-nuclearity molecular centres were detected. However, a weak singlet in the free-spin region grew in. This is tentatively assigned to conduction electron spin resonance (CESR) in pseudo-metallic, Ag0n particles. On further melting the Ag0n signal disappeared and the sample became black, indicating the eventual formation of colloidal silver. Similar reactions were observed in ethanol, ethane-1,2-diol and isopropyl alcohol.The allyl alcohol system did not give any clearly defined Ag° centres, only solvent radicals being observed at 77K. Two possible silver–solvent adducts were detected after annealing, one with a larger Aiso(Ag) value than expected (ca. 360 G). Results for propargyl alcohol were similar, except that only one silver–solvent species was formed. Possible structures for these centres are discussed. When both systems were annealed to the matrix softening point, the adduct signals decayed and an isotropic singlet in the free-spin region was revealed. This signal was particularly strong in the propargyl system. The g value and linewidth are similar to values recently reported for CESR signals from Ag0n latent-image particles formed in silver halide matrices by photolysis.

  高氯酸银在甲醇、乙醇、乙二醇、异丙醇、烯丙醇和炔丙醇中的溶液在77 K下暴露于60Co γ射线，并使用ESR光谱研究了产生的自由基。除了CH2OH溶剂自由基外，甲醇溶液还产生了AgII中心和一系列离散的Ag°物种。后者显示出不同范围的超精细耦合，反映了各种程度的溶剂化。它们的相对产率根据初始AgI浓度和添加的氯酸钠而变化。在退火至约120 K后，Ag°转变为分子簇阳离子Ag+2、Ag2+3、Ag3+4和Ag4+5，这些先前已在多种系统中通过ESR和光谱学鉴定，并显示是由AgI离子的连续加成形成的。Ag4+5的形成在高初始AgI或高配体（硝酸盐或高氯酸盐）浓度下更有利。在银聚合过程中，溶剂自由基(CH2OH)衰减，形成了加合物[AgCH2OH]+ [Aiso(Ag)= 128 G]。在退火至基质软化点时，这些物种消失。未检测到更高核的分子中心。然而，自由自旋区域中出现了一个弱单重态。这被暂时归因于伪金属Ag0n粒子中的导电电子自旋共振(CESR)。在进一步熔化后，Ag0n信号消失，样品变黑，表明最终形成了银胶体。乙醇、乙二醇和异丙醇中也观察到了类似反应。烯丙醇系统未产生任何明确的Ag°中心，仅在77K下观察到溶剂自由基。退火后检测到两种可能的银-溶剂加合物，其中一种的Aiso(Ag)值比预期的大（约360 G）。炔丙醇的结果类似，只是仅形成了一种银-溶剂物种。讨论了这些中心的可能结构。当两个系统都退火至基质软化点时，加合物信号衰减，自由自旋区域中显示出各向同性单重态。这个信号在炔丙醇系统中特别强。g值和线宽与最近报道的由银卤化物基质中的光解形成的Ag0n潜影粒子的CESR信号相似。
• Dynamics of O2 photodesorption from metal clusters: A significant difference from bulk behaviour
  作者：Marco Niemietz、Kiichirou Koyasu、Gerd Ganteför、Young Dok Kim

  DOI：10.1016/j.cplett.2007.03.016

  日期：2007.4

  size-selected AgnO2- cluster anions with n = 2, 3, 4 and 8 was studied using time-resolved photoelectron spectroscopy (TR-PES). The spectra indicate that relaxations of photo-excited AgnO2- clusters with n = even numbers accompany ultrafast direct O2 photodesorption. For the odd-numbered cluster Ag3O2-, in contrast, a long-lived excited state is observed, since O2 might be dissociatively chemisorbed, suppressing

   使用时间分辨光电子能谱（TR-PES）研究了n = 2、3、4和8的大小选定的AgnO2-团簇阴离子对O 2的光解吸。光谱表明，n  =偶数的光激发AgnO2-团簇的弛豫伴随着超快速直接O 2光解吸。相反，对于奇数簇Ag 3 O 2-，观察到长寿命的激发态，因为O 2可能被解离性化学吸附，从而抑制了氧气的直接光解吸。这两种，直接解吸和长寿命 从被吸附物覆盖的金属表面还没有观察到激发态，表明这种小团簇具有独特的光化学性质。
• Fluorescence and excitation spectra of Ag4 in an argon matrix
  作者：C. Félix、C. Sieber、W. Harbich、J. Buttet、I. Rabin、W. Schulze、G. Ertl

  DOI：10.1016/s0009-2614(99)01034-9

  日期：1999.11

  We report the fluorescence and excitation spectra of size selected Ag4 deposited in an argon matrix. The main fluorescence peak for Ag4 is observed at 458 nm. The excitation spectrum for this emission is in good agreement with recent theoretical calculations and photodepletion experiments.

  我们报告沉积在氩气基质中选定大小的Ag 4的荧光和激发光谱。在458 nm处观察到Ag 4的主要荧光峰。这种发射的激发光谱与最近的理论计算和光损耗实验非常吻合。
• A novel silver cluster
  作者：Robert Janes、Andrew D. Stevens、Martyn C. R. Symons

  DOI：10.1039/c39880001454

  日期：——

  The pentameric silver cluster, Ag54+, has been prepared in methanol and ethanol glasses at 77 K and characterised by e.s.r. and optical spectroscopies; the experimental parameters for this species are in close agreement with previous theoretical studies.

  五聚体银簇Ag 5 4+是在甲醇和乙醇玻璃中以77 K制备的，其特征在于esr和光学光谱。该物种的实验参数与以前的理论研究非常吻合。
• Silver clusters in rare gas matrixes. Thermal and photochemical silver atom aggregation reactions
  作者：Steven A. Mitchell、Geoffrey A. Ozin

  DOI：10.1021/j150651a039

  日期：1984.3