character and characterization
- 格式:ppt
- 大小:32.50 KB
- 文档页数:14


21卷1期 结构化学(JtEGOU HUAXUE) Chinese J Struct.Chem 、白1.2 No l 34~37 Synthesis and Structural Characterization of 【(矿.C5Me5)2Mo2Fe2S4Br2】① YU Hong JI Shun-Jun Lang Jian-Ping (Depm—tment oJ Chemistry and Chemical Engineering,Suzhou Universil)) Suzhou 215006,China) ABSTRACT The reactions of[(矿.c5Me5)Mo(S 13u)3】with equimolar FeBr3 in THF afforded a neutral tetranuclear cluster【(矿一c5Me5)2,Mo2Fe2S4B r2]1.The structure of 1 was determined by single-crystal X—ray difraction analysis 1 crystallizes in the monoclinic space group P2 u/n(No. 14)with a=9.69I(2),b=I 5.204(2),c=I8.850(2】A,卢=96 44(1)。, =2759.8(7)A ,z 4,尬 862 08,口=2.075 egcm . 000)=i680, (MoKa)=51.31 cm。。and r=296 2 K.Withthe use of 3667 observed reflections >3.oo ̄0),the structure was refined to R=0.041 and Rw 0.051. 1 is composed of a distorted Mo2Fe2S4 cubane core with two Br atoms and two 一CsMe5 groups coordinating at the Fe and Mo sites,respectively The lengths of Mo—Mo and Fe—Fe bonds are 2.826 and 2 773 A respectively the mean 1ength ofMo-Fe bond is 2.751 A Keyword:synthesis,crystal structure,molybdenum cluster,iron cluster 1 INTRoDUCT10N We once reported a C—S bond cleavage reaction of(rl5一C5Me5)Mo(S Bu)3,which led to a Mo(IV) thio/thiolate complex(叩5.C5Me5)MoS2(s’Bu)【I】- This reaction was facilitated by oxidants such as S8,gray selenium,and FeC1 The reaction with FeC13 gave rise to a cubane cluster [(矿一c5Me )2Mo2Fe2s4cI2】.which served as an excellent building block to construct various Mo/Fe/S clusters In this paper,we report the crystal str ̄mtLtre of[(矿一C sMe5 Mo2Fe2S4Br2] isolated from an analogous reaction of (r/s—C5Me )Mo(S’Bu)3 with FeBr3. 2 EXPERIMENTAL 2.1 Preparation of complex 1 Anhydrous FeBq added to a solution (O.059g,O.20mmo1)was of( .C5Me5)Mo(S Bu)3… r0.1 0g,O.20mmo1)in 20mL THF The mixture was ke:pt on stirring overnight to give rise to a dark red solution.After concentrating to ca 4mL,Eb_O (8mL)was added carefully oflto the surface ofthe solution,forming black prisms of 1 several days later The product was collected by filtration, washed with THF and Et2O.t}1en dried in V ̄ZblO. Yield:0.027g(3 1%based on Mo).Anal Calcd (%)for C2DH30B F0 M啦S4:C,27.86;H,3.51;S, 14.88 Found(%):C 27 83;H,3 50;S,15.28. IR(KBr pellet): Mo—S )425(w),409(w)cm。. 。H NMR(CDC13’500 MHz): 1.83(s,30 H, qLC 5Mes)(wfi2:38 Hz).Crystals suitable for X.ray analysis were obtained directly from the above preparation. Received 1 I April 200l accepted December 2001 ①This v,ork Was suppoaed by the Key Laboratory ofOrganic Chemist ̄of Jiangsu Pmvince at Suzhou Un vers ty ( ̄)Authortowhom corr ̄pondence should be addressed E-mail:.jplmlg@suda edu cn Tel:I)51 2-Sl12 7 First authol Yu Irong,born in 1967;n s Lecturer.maJonng Ill synthesis Ol’new metal sulfide compl
正面描写和侧面描写写人物作文
英文版
Character Description: Writing about a Person
When it comes to writing about a person, there are two main ways to approach it:
through direct or indirect characterization. Direct characterization involves explicitly
stating the traits and qualities of a character, while indirect characterization involves
revealing these traits through the character's actions, thoughts, and interactions with
others.
In a direct characterization, the writer may describe the physical appearance,
personality, and background of the character. For example, they may say that the
character is tall, with blonde hair and blue eyes, and is known for being kind and
generous. This type of description gives the reader a clear picture of who the character is
and what they are like.
On the other hand, indirect characterization requires the reader to infer the traits of
Characterization in “A Rose for Emily”
Thesis: By means of the characterization in “A Rose for Emily”, the author depicts an
image of declining aristocrat, Emily. She represents the decayed tradition of the south.
Through her tragic life and the contrast between the past and the present, the author
implies the change with time and the loss of traditional ideas.
Outline
Introduction
I. Characterization by Telling
A. Characterization through appearance
B. Characterization through others
II. Characterization by showing
A. Characterization through dialogue
B. Characterization through actions
Conclusion
Abstract:Emily, a declining aristocrat, kept her patrician dignity and refused to
communicate with others, which caused the tragedy. The death of Emily represents
the loss of the tradition and culture of the south.
characteristic词根词缀
1. 什么是characteristic词根词缀?
在语言学中,characteristic(特征)是一个常见的词汇。它可以用作名词,形容词或动词,用来描述个体或事物的特点、属性或特征。而在构成复杂单词时,characteristic可以作为一个词根或词缀。
2. characteristic作为一个独立的单词
作为一个名词,characteristic表示某个事物或个体所具有的独特性质或特征。这个特征可以是显著的、重要的或典型的。
例如: - “Honesty is a characteristic that is highly valued in a
person.” - “The blue color is a characteristic of the sky.”
作为形容词,characteristic表示某个事物具有独特性质或特点。它常被用来描述某个人、事物或情况。
例如: - “Her characteristic smile brightened up the room.” - “The
artist’s paintings are known for their characteristic style.”
作为动词,characteristic表示将某种特征归因于某个人、事物或情况。
例如: - “The success of the project can be characteristic to the
team’s hard work and dedication.”
3. character-作为一个前缀和后缀
在构成复杂单词时,characteristic可以被用作前缀或后缀,以赋予单词更多的含义。
3.1 character-作为前缀
当character-作为前缀时,它可以表示”特殊的”、“独特的”或”典型的”。
例如: - “Character-building activities help students develop important