Frank Lloyd Wright :: essays papers

Frank Lloyd Wright Frank Lloyd Wright was an architect who was a pioneer in modern style, and he is considered one of the greatest figures in architecture in the 20th-century. In Richland Center, Wisconsin on June 8, 1867 Wright was born. 17 years latter at the University of Wisconsin his interest in architecture had already shown itself. He enrolled in civil engineering because the university didn^t offer any classes for his chosen field. He gained some practical experience by working on a construction project for the university part time. He left school and went to work for the firm of Adler and Sullivan in 1887. Louis Sullivan from the firm had a profound in Wright work. He left the firm and went to make his own office in Chicago in 1893. Organic architecture was a philosophy created by Wright. It means that a building should be developed out of it^s natural surroundings. Originality was shown in his designs for public and private structures. The ornate neoclassic and Victorian styles favored by conventional architects was the kind of thing Wright rebelled against. Wright was opposed to the mechanical imposition of preconceived styles. The particular function of the building, it^s environment, and the type of materials employed in the structure should be the things that ultimately determined the architechtual form is what Wright believed in. One of the many fundamental contributions was the use of building materials for their natural colors s well as structural characteristics. With the open planning of one room flowing into another his interiors emphasize the sense of spaciousness. Precast concrete blocks reinforced with steel rods was one of the many new techniques Wright initiated. Air conditioning, indirect lighting, and panel heating were a few of the numerous innovations Wright invented. One of Wright big feats was to make the Imperial Hotel in Tokyo. The building was made to withstand earthquakes. One year after being completed it suffered no damage from a disastrous earthquake. Architects who were more conventional then Wright were against his different ways all thorough out his career. He went into exile for a year in Europe because of personal difficulties and professional antagonisms. Upon his return he began a new career of ever widing-achivments. Some of his later works are the Millard House; the Kaufmann House; called Falling Water; The Johnson Wax Company Administration Building; the First Unitarian Church; the V.C. Morris gift shop; and the Price

History of immigration

Your huddled masses yearning to breathe free, the wretched refuse of your teeming shore. Send these, the homeless, tempest-tots to me, I lift my lamp beside the golden door! † Do our immigration policies still honor the words written by Emma Lazarus in 1883 on the base of the Statue of Liberty, and if so, what impact do they have on our economy?The issue of whether our economy is impacted negativity or positively by undocumented workers and what should be done about It Is a widely debated topic in this country right now and reported about on every form of media (news, print, social) available on a dally basis. The Issue of undocumented Immigration Is Important; It concerns fundamental, moral and economic questions about how we deal with Immigration In our country. Various arguments have been presented about this issue.We will consider the argument from people who feel the undocumented workers negatively affect the economy, why those views are flawed, review the evolution of imm igration along with immigration policies and what are in effect presently, what policies would promote change regarding immigration, as well as how we can build a bridge between the two arguments. I will then put forward suggestions for the introduction of ways in which we can begin the changes in policy to best suit both sides of the argument. It has been argued that undocumented workers drain the economy and Just benefit a few businesses at the expense of Americans citizens.An article written by Steven Amalgam, published in the City Journal summer 2006, supports the belief : â€Å"unskilled, undocumented workers benefit a handful of Industries by getting low cost labor, and the taxpayers foot the bill. † In other words, undocumented workers and their illegal families are a drain on our economy. It is claimed that they send every penny they earn to their country of origin, use public services they are not entitled to, perform menial labor, do not pay taxes and their children abuse the right to public services and education.However, as the pamphlet by Neighborhood center states: † in fact there is no question as to the importance of the buying power of undocumented immigrants. The real predictor of wage disparity is not whether someone is an immigrant (regardless of status), it is lack of education. Foreign-born entrepreneurs with startups businesses have been behind 25 percent of these businesses in this country. Three quarters of the undocumented Immigrants pay payroll taxes and they contribute $7 billion In Social Security funds annually without the ability to collect Social Security.While the majority of the children of undocumented Immigrants are born here legally and are eligible to public services and education, their parents for fear of deportation are negative impact on the economy is Just a myth; there is a net benefit to the nation's total economic output raising it by a reported $21. 5 billion per year (USA Today). In addition, accordi ng to a study by the investment research company, Standard & Poor's, â€Å"the cost of providing services to undocumented workers is largely offset by the economic benefits they generate. We can see why if you look at the economic effect on the country without researching your views toughly, on the surface you may be able to put together a shaky argument, but after researching the facts you do see that undocumented workers actually boost our economy, as we see in Gordon H. Hansom's, The Economics and Policy report of illegal immigration in the United States; â€Å"the current regime of illegal immigration, despite its faults, has been efficiently beneficial to US employers that they are doubtful about the capacity of Congress to improve the situation and therefore unwilling to take the political risk of supporting reform.The collected taxes impact our economy now while baby boomers are starting to collect their Social Security benefits they boost the system by the unconvertible fu nds of undocumented workers. † Before we can understand how we arrived at the present immigration policies here in America, we must look back at the evolution of immigration and immigration policy from the 1600 to present time. Our long economic history in America has been shaped by the groups of immigrants that have settled here, what contributions to the economy they brought with them and how the immigration policy changed in response to the influx of each group of immigrants.We will start our review looking at a few immigration groups, the changes made to our immigration policies starting with the English Settlers with traders and their contributions to the economy to present day influx of Middle Eastern and Latin origin immigrants benefiting our economy with access to low cost and back breaking labor. In the 1600 hundreds the traders that were brought by the English settlers not only brought the spices and hard goods to trade, they brought slave labor for trading as well.T his group, African slaves would grow quickly to 20 percent of the population providing cheap labor, and since they were considered property, they were not allowed to be naturalized till 1870. Many different groups came and made contributions to the economy of cheap labor with their meat processing skills, work ethic and willingness to take on highly dangerous back breaking Jobs. With each new group the policy changed; the first immigration law enacted in 1790 (after nearly a century of unregulated immigration and massive economic growth) began defining and restricting citizenship to the United States.The act of 1790 was revised, further restricting and adding requirements for obtaining citizenship. The Asian immigrants experienced a similar exclusionary period as did the Africans; they were allowed to live in the US but were not allowed to become citizens until 1943 when the Chinese Exclusion Act of 1882 was repealed. President Ronald Reagan was instrumental in bringing forth the Im migration Reform and Control Act of 1986.Many revisions have been made to the immigration laws, but t was never as publicized as after September 1 1, 2001 when fear of Terrorism brought the need for reform so we can exclude individuals suspected to be terrorists. Presently the immigration laws are not an easy path to becoming legal and are not family friendly because they separate parents from their American born children Just life. â€Å"America's immigration system is outdated, unsuited to the needs of our economy and to the values of our country.We should not be content with laws that punish hardworking people and deny businesses willing workers and invite chaos at our borders. † George W. Bush, February 2, 2005. George w. Bush and Barack Obama did not agree on many things, but â€Å"They share a belief that the high levels of illegal immigration are an indication of the current policy being broken, and that immigrants by and large make a positive contribution to America. â€Å"We need immigration reform that will secure our borders, and†¦.. That finally brings 12 million people who are here illegally out of the shadows†¦We must assert our values and reconcile our principles as a nation of immigrants and a nation of laws. † Barack Obama, June 28, 2008. Two Presidents, from two different political parties, with very efferent political views share the same view that our immigration system is broken. What changes should be made to the immigration policy here in America? How will those changes affect the economy? What is the moral impact on families? These are questions which divide many; philosophers, labor unions, political parties, the people within political parties, the people in nail salons and Americans in general.Peter Brooklime (1999), a political philosopher, a ND supporter of placing restrictions on immigration that would all but end immigration to this country, believes the current immigration policies second guess the Ameri can people and Jeopardize our nation. Brimless beliefs historically were supported by Labor unions and their leaders, yet even these groups are realizing that the number of immigrant union members has been rapidly increasing (Migration Policy institute 2004) and if they do not begin to embrace the immigrants a large number of their membership base will disappear and possibly their existence as well.To the other extreme, Walter Block argues â€Å"like tariffs and exchange controls, migration barriers of whatever type are egregious locations of laissez-flare capitalism† (Block 1998; 168). The Democratic Party says they support â€Å"immigration reform† and point fingers at the Republican Party for not having it done yet. Ironically, a Republican President supported and pushed for the most encompassing reform possible â€Å"Amnesty in 1996†. We need to arrive at a compromise of the two schools of thought.Yes we do have to protect ourselves from terrorists and crimi nals, but not at the cost of our crops not being picked or produce being too high to purchase, our manicures and pedicures getting out of control price sis or our restaurants having to raise prices so high only the rich could afford to eat out. We need to also morally take into consideration families. Why should I, a second generation American( paternal side of my family) and a multi generation American( on the maternal side of my family), with children who are first generation Americans be denied my late mother in law to visit and stay with us as long as is mutually agreed upon.The Consulate in Ecuador at first denied us a visa for my Mother in Law. I had to fight for my rights as an American to bring her home with me. They only gave her a 3 month visa. I also had to close my eyes after the three month visa expired to her being illegally in America. So America's immigration policy made this grandmother a criminal. While we ponder on what to do about immigration we must control ours elves from falling subject to xenophobia, misconceptions and political rhetoric.We do need to continue with researching the brings forth in their applications to come to America or that are here presently â€Å"illegally'. The paperwork involved should not be so difficult that we only further the economy by creating further Jobs in the immigration law field. If you have family here already and have been contributing to our economy through your hard work, contributing to our economy through your spending power and good civic behavior, why should you have a difficult path to legalization?Simplify paperwork, intensify background checks of those applying and their family members here and in their country of origin, require medical examination and community service components in the legalization path. Allow those that are here to pay a nominal fee, submit simple applications to change their immigration status from illegal to in process of globalization and come out of the shadows. This will really protect our borders by knowing who is here amongst us.Willingness to do good works for the many non- profit organizations that exist should be much more important than your financial resources in your country of origin in any path to legalization. Policy should be put in place allowing immigrants here to move from â€Å"illegal† to citizen in a reasonable amount of time with the before mentioned components built in so we can weed out the criminals not willing to live by our laws and contribute to our society and support he growth of our country, while rewarding the immigrants that with their diversity and civic responsibility add to the strength of our country.These policies would improve the type of applicant, reduce need for expense of immigration lawyers, and reduce the need to spend on expensive man power in INS offices, and embassies, move the emphases on skilled, community minded, productive, family oriented immigrants willing to pay their taxes and contribu te to diversity and economic growth of our wonderful country. We need to build a bridge between the main two arguments of public safety nickering terrorists and Jeopardizing our economy, as well as moral fiber with policies that will have protections of the many while also representing the fiber that made our country what it is.Allowing the right wing to impose restrictions on immigration based on fear is not in the best interest of our country. In conclusion, we are a nation of immigrants. The only Americans that truly belong here is those with Native American Indian ancestry. The rest of the American population is either descendents of immigrants or immigrants themselves; some by choice and others forced to migrate due to refugee, slavery etc. Our Country was made by immigrants, and this is a supporting case point to continue allowing immigration at a fairly high level.

Leadership As A Charismatic Leader - 1541 Words

Numerous of leaders especially in the church are considered charismatic. Before the 1980’s, charisma was not a major topic of discussion. The Charismatic approach is measured to reflect a particular kind of leader. They are usually strong self-confident individuals that portray competency. Their followers tend to mimic the goals and leadership style of the charismatic leader. They are gifted in articulating their ideas, â€Å"plans and goals to others while creating an ambiance that says, do as I do. They can articulate a compelling or captivating vision and can arouse strong emotions in followers. Despite the controversy about the originality of the charismatic leader, they are effective in the church, politics, and the business†¦show more content†¦The paper clarifies this thought by sharing the beginning of many notable individuals’ leadership style and how they matriculated to the office of the President of the United States and renowned Civil Rights Leaders. The Christian Worldview is shared that good leadership is defined one’s relationship with God and how we treat one another. It provides information about biblical leadership such as David, Jesus, and Paul whose leadership approach is charismatic and remains effective today in many churches. It further talks about the charismatic approaches of men like Martin Luther King Jr. and John F. Kennedy, Barak Obama who swept the nation off their feet because of the resounding eloquent speeches that many young and old now recite and hold true to their hearts. Moreover, this paper speaks about some twenty-first century charismatic leaders such as Martin Luther King Jr., Barak Obama, and Bill Clinton. Details are provided to show that Charisma is a process, which links the traits of the charismatic leader to a VABES while influencing others to follow their way of thinking when using a burst of energy. Are Charismatic Leaders Born or Made? First and foremost, charisma in the Greek means â€Å"divinely inspired gifts,† only God can give these kinds of gifts. Because high self-confidence and strong conviction in one’s beliefs is a given factor for the charismatic leader, I argue that they are born, with leadership abilities that require development andShow MoreRelatedCharismatic Leadership : A Charismatic Leader1603 Words   |  7 PagesCHARISMATIC LEADERSHIP In the current leadership era, Charismatic leadership is one of the newer leadership perspectives. This approach is based on the concept of charisma, which means â€Å"an inspired and divine gift†. Elements of a charismatic leadership A charismatic leadership is characterized by these three elements: Leader characteristics, Follower characteristics, and Situational Factors. Notice that these elements are much like the elements that contribute to the cycle of abuseRead MoreCharismatic Leadership : A Charismatic Leader862 Words   |  4 PagesCharismatic Leadership A charismatic leader has the ability to create an impression of themselves that promote the desired image of themselves, their vision, or their organization (Durbin, 2013). This paper will identify what traits a charismatic leader possess and analyze these traits with my own to determine the level of charisma I have or if they are obtainable with change. The charismatic leader in modern-day times is a conception of society. So as not to appear as an everyday leader, he isRead MoreCharismatic Leadership : A Charismatic Leader709 Words   |  3 PagesThe charismatic leadership approach is dependent on the captivates and articulateness of the leader; charismatic leaders are compelled by their passions and dedication to their reason. Charismatic leaders correspondingly are occasionally known as transformational leaders since they share several relationships. Their principal dissimilarity is emphasis and audience; charismatic leaders frequently attempt to make the present circumstances pleasanter, whereas transformational leaders emphasize on convertingRead MoreCharismatic Leadership : A Charismatic Leader1150 Words   |  5 PagesCharismatic Leadership Charismatic leadership uses â€Å"impression management to deliberately cultivate a certain relationship with group members† (Dubrin,2010, p. 68). They create a positive vision for their followers and these followers will work diligently to make the visions of the charismatic leader come true. This leader can influence external stakeholders by becoming the symbol of the company or cause he represents. â€Å"Charismatic leaders can transform organizations through their ability to seeRead MoreCharismatic Leadership : A Charismatic Leader960 Words   |  4 PagesCharismatic Approach A leader is described as one who influences others to attain goals. Leaders orchestrate change, set direction, and motivate people to overcome obstacles and move the organization toward its ideal future (Bateman, T. and Snell, S., 2013, p.460). Out of the three leadership styles our team researched, Jesus leadership style was seen more in the Charismatic Approach: (House’s Theory of Charismatic Leadership). When a leader possess charisma, one should be Dominant, and self-confidentRead MoreLeadership As A Charismatic Leader1495 Words   |  6 Pages Today in society we see many leaders in this chaotic world we live in today. Leaders have to deal with tricky situations no matter the circumstances. Everyone including leaders desire to work in a drama free and less negative establishment. However, an effective leader must be able to with handle problems or issues. A leader have to learn how to adapt and adjust, guide their counterparts which leads to productive environment. Charismatic leader helps produces a pleasurable environment to createRead MoreHuman Leadership: The Importance of Charismatic Leaders in an Organization950 Words   |  4 Pages1.0 Introduction In human, leadership is a complex activity which shows different characteristics in different situations (Keohane, 2005). The activity that was conducted in the class showcased different characteristics in participants when it came to leadership. The game was mainly for the participants to understand the qualities and knowledge when it comes to leadership. 1.1 The Game In this report I am going to talk about two persons myself and Mario Doe. The tag that I received wasRead MoreCharismatic Leadership And Transformational Leadership869 Words   |  4 Pagestheories have largely shaped the conversation around charismatic leadership, providing the theory with context and testable characteristics. The two theories, along with other research in the leadership model, have revived the trait-based approach to leadership. Since charismatic leadership is linked with personal traits and the transformation of subordinates, the current conversation around the model often links it with transformational leadership theory. Both of these theories seek radical changesRead MoreAdvantages And Disadvantages Of Charismatic Leadership913 Words   |  4 Pagesdisadvantages of charismatic leadership Charismatic leadership is among the leadership theories that can be both a blessing and a curse to an organisation. A strong vision with emotional influences can be force for positive change, such as the example of Martin Luther King’s civil rights movement, but it can lead to darkness as well. Advantages of charismatic leadership As mentioned above, charismatic leadership can at its best be an inspiration style to lead. A successful charismatic leader is able toRead More Leader Characteristics Essay1736 Words   |  7 PagesLeader Characteristics Charismatic leadership is one of four subdivisions of the larger concept of transformational leadership (Bass, 1990). Charismatic leaders are self-confident, dominant, purposeful, articulate, influential, idealistic, and expressive. They have high energy levels, strong convictions, the ability to display empathy, and are risk takers (Bass, 1990). By stimulating ailing corporations, revitalizing aging bureaucracies or launching new enterprises (Howell and Avolio, 1995)

Sociology

Personal Narrative Curiosity Killed The Cat - 881 Words

â€Å"Curiosity killed the cat.† (Anonymous) I believe that was my parents’ perspective on life. In Indonesian custom, the young has to respect the elders, which include parents and teachers. Asking questions or questioning them was considered disrespectful. Holding on to that tradition, my parents taught me to hold on to my curiosity. This upbringing affected every aspect in my life, including my learning style and career options as well. I came from a long line medical field family from my mother side. My mother wanted me not to border the line of curiosity and stay within the cul-de-sac continuing the family tradition by becoming a doctor, a nurse, a midwife, or a pharmacist. During my school years, if anybody asked what I wanted to be when I grew up, of course my answer was to become a doctor. It was instilled in my mind, or so I thought until I met Mr. Tahyana and Aisha who had made a different in the way I view my life. My mother put me on rigorous daily routine of practicing math skills and science since early age . She believed that by mastering these subjects, I would have better chances in the future. I was in a confinement. This over powering method of parenting finally took a toll on me. It seemed that everything I did was not good enough for her. My hatred towards learning started to grow. School became so daunting, that I dreaded coming to school. I couldn’t concentrate, and slowly my grades were getting lower. In the midst of frustration, a friend of mineShow MoreRelated Japanese Alien and Japanese-American Poets In U. S. Relocation Camps4710 Words   |  19 Pagessome of the poetry also illustrates how, even though they might have been angry, the Japanese aliens and Japanese Americans acted very compliantly, having faith in their country that the situation would get better. One of the characters in Littles narrative poem muses I do not understand / at all, but if we must / go somewhere to serve / our country / then we must. Orders / are to be obeyed. Research on the subject r eveals, surprisingly, little resistance to the orders, with few instances of publicRead MoreLangston Hughes Research Paper25309 Words   |  102 Pagesstayed with his grandmother in Lawrence, Kansas. Grandmother Mary Langston, an American citizen of French, Cherokee, and African descent, was nineteen in 1855 when men tried to kidnap her and sell her as a slave. Her first husband, Lewis Leary, was killed in 1859 at Harpers Ferry, West Virginia, during John Browns raid on the federal arsenal. Throughout Mary Langstons life, she treasured Lewiss bullet-riddled shawl, an emblem of his martyrdom. She often covered young Langston with it as he sleptRead MoreLogical Reasoning189930 Words   |  760 Pagesthe same experience. When you hear the details, you understand why. The symptoms are chronic diarrhea, abdominal cramps, bloating, and fatigue. Also, she says, the park signs about Giardia are probably posted because the organisms cannot be killed by boiling. However, she admits that she isnt sure of her interpretation of the sign, and she agrees with Emilio that the nearby stream might not even contain Giardia, so she decides to do whatever the majority wants. She adds that the threeRead MoreIgbo Dictionary129408 Words   |  518 PagesPart II (1913) consists of an English-Ibo and Ibo-English dictionary, based on the Awka and Onitï€ ¬sha dialects. It has a rather complex and non-phonemic transcription of the vowels; tone is partially marked. Part III (1913) consists of Proverbs, narratives, vocabularies and Grammar, the vocabularies being of Awka, OniÄ a (Onitsha), Abo (Aboh), Ivitenu, and á »Å'jà ¡ (the last two being apparently extreme northern dialects). These vocabularies are based on the same list that Thomas uses in his SpecimensRead MoreSecurity Forces51988 Words   |  208 PagesMaintenance Conduct checks of assigned equipment to include all Surveillance, Target Acquisition, Night Observation Equipment and Communications. Perform Personal Hygiene Personal hygiene (cleanliness) practices safeguard health by protecting against the spread of disease causing germs. Improve Camouflage Continually reapply and imp rove personal and equipment camouflage to avoid being detected from the enemy. NOURISHMENT/RATIONS Issued MREs have the essential substances, in the right amounts and balanceRead MoreOrganisational Theory230255 Words   |  922 Pagesoutcomes. These learning outcomes provide a guide to the different sections of the chapter. Stop and think Each of the chapters contains ‘stop and think’ boxes. These are designed to form the basis for brief discussion amongst group members or for personal reflection on some key issue raised in the text. Case studies These are designed to enable the reader to relate theoretical issues to organization practice, or to give a practical organizational example. Ideas and perspectives These are designedRead MoreStephen P. Robbins Timothy A. Judge (2011) Organizational Behaviour 15th Edition New Jersey: Prentice Hall393164 Words   |  1573 PagesLeaders 399 Case Incident 1 Leadership Mettle Forged in Battle 400 Case Incident 2 Leadership Factories 400 13 Power and Politics 411 A Definition of Power 412 Contrasting Leadership and Power 413 Bases of Power 414 Formal Power 414 †¢ Personal Power 415 †¢ Which Bases of Power Are Most Effective? 416 †¢ Power and Perceived Justice 416 Dependence: The Key to Power 416 The General Dependence Postulate 416 †¢ What Creates Dependence? 417 Power Tactics 418 Sexual Harassment: Unequal Power inRead MoreFundamentals of Hrm263904 Words   |  1056 Pageswealth of interactive visual and audio resources, WileyPLUS gives you everything you need to personalize the teaching and learning experience.  » F i n d o u t h ow t o M A K E I T YO U R S  » www.wileyplus.com ALL THE HELP, RESOURCES, AND PERSONAL SUPPORT YOU AND YOUR STUDENTS NEED! 2-Minute Tutorials and all of the resources you your students need to get started www.wileyplus.com/firstday Student support from an experienced student user Ask your local representative for details!

Children With Emerald Eyes Essay Research Paper free essay sample

Children With Emerald Eyes Essay, Research Paper Children With Emerald Eyes By Mira Rothenburg My book Children With Emerald Eyes, is about many kids, but focused around three kids placed in an establishment, due to schizophrenic and autistic conditions. These kids? s names are Sara, Chaim, and Danny. The scene of this narrative is in an institute for the insane, schizophrenic, and autistic. Most of these kids are orphans, or kids, that have escaped from their county, and are seeking to happen safety. I feel that their struggle is truly, between themselves. I mean that the chief job is them. They, Danny, Sara, and Chaim are their ain job. They are seeking to run from themselves, but they can? t. In my book there were three different lifting actions, one for each kid. The first lifting action started during Danny? s portion of the book. The lifting action was when he was seeking to interrupt down the emotional walls that his old ways had built. We will write a custom essay sample on Children With Emerald Eyes Essay Research Paper or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Sara? s lifting action started when they described how she was ever desiring everything wrapped, like a present. Following is the lifting action found in Chaim? s narrative is when he got nervous and tried to literally take a bite of himself. The chief characters of this book is Mira, the psychologist and besides the writer of this book. I would name Mira the supporter, because she was the lone 1 who would believe in the fact that these childs could be helped, and she enjoyed making it. At the beginning of the book though, the kids were the adversaries. Throughout the narrative, there was allot of character development, non merely from the kids, but from Mira besides. Through all of the narrative the point of position stayed at a camera 3rd individual. The subject the writer nowadayss, is that of love, fright, friendly relationship, treachery, turning up, and a hunt for one? s ego. I feel that the most of import message of this book is that even though one can experience betrayed by person, there can still be friendship between them. My sentiment of this book is one a miss normally have towards person or something, but I think that this book was really traveling. I feel that it touched base on everything a book should. There wasn? t really many things I didn? Ts like about this book except the point that it rather difficult to follow. As a affair of fact it has, it has changed the ways I look at the manner mentally challenged kids act.

Particle in a Box Experiment Essay Example

Particle in a Box Experiment Essay The visible absorption bands or conjugated dye arise from electron transitions involving the electrons in the conjugated and they are free to move along the chain and are not attached to any atom. An example of such a dye is 3,3-diethyl-thiacyanine iodide. The cation has two resonance forms causing each of the bonds in the conjugated chain to have an order of 1. 5 and have a length similar to the C? C bond length in benzene. We will assume that the potential energy is constant along the chain and sharply rises to infinity at the ends.Therefore, we can replace the electron system by free electrons moving in a one dimensional box of length . Objective: The purpose of this experiment is to obtain the visible spectra of several cyanine dyes and then interpret them to a simple model of the electronic structure of the ? system: the Particle in a Box. Theoretical Model â€Å"Particle in a Box† In the Particle in a Box model, all potential energy interactions are assumed to be zero (c onstant) along the chain except at ends of the chain where the potential energy abruptly goes to +?. If a particle moving freely along the length of the box the energy an be calculated as : E = n2h28mL2 + V n = 1, 2, 3 †¦ (1) where n is an integer positive quantum number, h is Planck’s constant, m is the mass of the particle and L is the length of the box. If we assume that the most intense band in the experimentally observed spectrum can be interpreted as absorption of electromagnetic radiation by an electron as it is promoted from the HOMO to the LUMO, we can derive the following expression for the energy absorption ? E. E =h2 [2ni+ 1]/ (8mL? ) (2) he absorption wavelength for the HOMO _ LUMO transition is given by: ? = 8mcL? /h (2ni + 1) ni = p p = #e/2 (3) Therefore, the Particle in a Box model predicts that the wavelength of the absorption maximum is a function of chain length (L) and number of p-electrons (N). The adjustable parameter Lmax can be calculated as: ? = 8mc/h(2p+1)[(2p-1)Lb + Lext]2 (4) ?max h/8mc=[2p-1Lb + Lext ]2/ (2p +1) (5) Procedure: In this experiment, we used the following dyes. Dye #1: 3,3-diethyl-thiacyanine iodide (yellow) Dye #2: 3,3-diethylthiacarbocyanine iodide (Pink)Dye #3: 3,3-diethylthiadicarbocyanine iodide (Blue) Dye #4: 3,3-diethylthiatricarbocyanine iodide (Olive) We placed 0. 3 ml of dye solution in the 1- cm cuvette and added 3. 00 ml of water and mixed well. Using the nano drop spectrometer, first cuvette with water was used as a blank and later second Cuvette with dye solution was inserted and measured the absorbance of the sample. Once our absorbance of the highest peak was less than 0. 5 and the absorption spectrum of each dye was between 400-800 we collected the data. Notes On Wavelength:If only changes in electronic energy accompany absorption of light, a very sharp maximum in absorption should be observed at the characteristic wavelength. Although sharp lines are observed for isolated atoms, broad ab sorption bands are observed for substances in liquid phases (due to the accompanying vibrational and rotational transitions). In the experiment, we shall assume that the wavelength ? max, the wavelength at which the dyes absorb most strongly, is the wavelength to use in the equation (5). Data/Result: A UV-Vis absorbance spectrum (Fig 1) was obtained and used to calculate experimental ? ax values for each of the studied cyanine dyes. Fig 1: UV Absorbance Spectrum for Dye 5d, Dye 6, Dye7 and Dye 8b Collected from Nanodrop Based on the data: Dye | Emprical formula | ? max /nm | Lit ? max| 3,3-Diethylthiacyanine Iodide| C19H19IN2S2| 417| 423| 3,3-Diethylthiacarbocyanine Iodide| C21H21IN2S2| 549| 556| 3,3-Diethylthiadicarbocyanine Iodide| C23H23IN2S2| 564| 652| 3,3-Diethylthiatricarbocyanine Iodide| C25H25IN2S2| 744| 757| In order to experimentally to calculate the Lext a plot of h ? 8mc experimental bond length, and P the number of the c atoms in conjugated system (N / 2) was constructe d. Dye| ? (m)| N| h (j. s)| m(Kg)| C (m/s)| h? /8mc| p| 5d| 0. 000000417| 6| 6. 62E-34| 9E-31| 3*10^8| 1. 27803E-19| 3| 6| 0. 000000549| 8| 6. 62E-34| 9E-31| 3*10^8| 1. 68258E-19| 4| 7| 0. 000000564| 10| 6. 62E-34| 9E-31| 3*10^8| 1. 72856E-19| 5| 8b| 0. 000000744| 12| 6. 62E-34| 9E-31| 3*10^8| 2. 28022E-19| 6| Using Regression Wizard: | | | | | y = (((2*x -1)*(0. 139*10^-9) + L)^2) /(2*x+1)| | | | |   | | reduced Chi-square| SDR| sum of squared errors| r^2| | | 4. 6915E-10| 6. 6031E-19| 0. 636| | | Covariance Matrix|   | | |   | | | L|Parameters| Initial Value| Optimized Value| Standard Deviation| | L| 3. 2614E-4| L =| 1. E+0| 6. 1243E-5| 1. 8059E-2| | | | | | | | | | | | x| y| y_calc| error| | 3| 1. 27803E-19| 5. 35822E-10| -5. 3582E-10| | 4| 1. 68258E-19| 4. 16754E-10| -4. 1675E-10| | 5| 1. 72856E-19| 3. 40984E-10| -3. 4098E-10| | 6| 2. 28022E-19| 2. 88527E-10| -2. 8853E-10| | | | | | | | | | | | | | | | | | | | | | | | | | | Lb= 1. 39E-10 Calculation of Lext based on equati on (5) Dye| P| ? (m)| ((2p-1)*0. 139*10^-9 +Lx)^2/(2p+1)| 5d| 3| 4. 17E-07| 2. 51*10^-10| 6| 4| 5. 9E-07| 2. 56*10^-10| 7| 5| 5. 64E-07| 1. 72*10^-10| 8b| 6| 7. 44E-07| 1. 92*10^-10| Uncertainties in ? max: See the attachment Conclusion: The spectrum obtained from Nanodrop revealed that 3,3-Diethylthiacyanine Iodide and 3,3-Diethylthiacarbocyanine Iodide have fairly broad spectral band compare to, 3,3-Diethylthiadicarbocyanine Iodide and 3,3-Diethylthiatricarbocyanine Iodide. This can be due to the electronic transitions from state to state which occur within a time interval much shorter than that of a molecular vibration and also experimental error was responsible for the lack of resolution.The collected electrically spectra were useful in comparison of experimentally and theoretically predicted ? max values and it shows that the experimentally determined values are close to the predicted value. Extracting Lext from equation (5) for each dye doesn’t follow the observed trend in the absorption maxima. For 3,3-Diethylthiacyanine Iodide and 3,3-Diethylthiacarbocyanine Iodide dyes as ni increases Lext and ? max increases and in 3,3-Diethylthiadicarbocyanine Iodide and 3,3-Diethylthiatricarbocyanine Iodide, Lext decreases as ni increases. The experimentally calculated Lext for compounds 1-4 was determined to be 6. 2E-5 m which doesn’t seem sensible. Large differences existed difference between the calculated effective box length compare to lb. From the experimental evidence and analysis, we don’t except the particle in a box model to be an appropriate one to describe the spectra of cyanine dyes. Since the errors in the ? max are not normally distributed experimental errors.Work Citedhttp://homepages. gac. edu/~anienow/CHE-372/Labs/Example. pdf http://homepages. gac. edu/~anienow/CHE-372a/Labs/Conjugated%20Dyesa. pdf