Phases of Liquid Crystals

Phases of Liquid Crystals Introduction to Liquid Crystals A liquid crystal is a thermodynamic stable phase characterized by anisotropy of properties Without the existence of a three-dimensional crystal lattice, generally lying in the temperature Range between the solid and isotropic liquid phase, hence the term mesophase. Liquid crystal materials are unique in their properties and uses. As research into this field Continues and as new applications are developed, liquid crystals will play an important role in Modern technology. This tutorial provides an introduction to the science and applications of these materials. The term liquid crystal signifies a state of aggregation that is intermediate between the crystalline solid and the amorphous liquid. As a rule a substance in this state is strongly anisotropic some of its properties and yet exhibits a certain degree of fluidity, which in some case may be comparable to that of an ordinary liquid. The first observations of liquid crystalline or mesomorphic behaviour were made towards the end of the last century by reinitzer and lehmann. What are Liquid Crystals? Liquid crystal materials generally have several common characteristics. Among these are a rodlike molecular structure, rigidness of the long axis, and strong dipole and/or easily polarizable substituents. A dipole is present when we have two equal electric or magnetic charges of opposite sign, separated by a small distance. In the electric case, the dipole moment is given by the product of one charge and the distance of separation. Applies to charge and current distributions as well. In the electric case, a displacement of charge distribution produces a dipole moment, as in a molecule. The distinguishing characteristic of the liquid crystalline state is the tendency of the molecules (mesogens) to point along a common axis, called the director (the molecular direction of preferred orientation in liquid crystalline mesophases). This is in contrast to molecules in the liquid phase, which have no intrinsic order. In the solid state, molecules are highly ordered and have little translational freedom. The characteristic orientational order of the liquid crystal state is between the traditional solid and liquid phases and this is the origin of the term mesogenic state, used synonymously with liquid crystal state. Note the average alignment of the molecules for each phase in the following diagram. A mesogen is rigid rodlike or disclike molecules which are components of liquid crystalline materials. It is sometimes difficult to determine whether a material is in a crystal or liquid crystal state. Crystalline materials demonstrate long range periodic order in three dimensions. By definition, an isotropic (Having properties that are the same regardless of the direction of measurement. In the isotropic state, all directions are indistinguishable from each other)liquid has no orientational order. Substances that arent as ordered as a solid, yet have some degree of alignment are properly called liquid crystals. Liquid Crystal Phases Liquid crystal phases are formed by a wide variety of molecules. They can be divided into two classes, thermo tropic and allotropic. Transitions to thermotropic phases are initiated by changes in temperature, while those to lyotropic phases can also be initiated by changes in concentration. Thermotropic Phases Thermotropic liquid crystals can generally be formed by prolate (calamitic) molecules or oblate (discotic) molecules. Liquid crystal phases formed by calamitic molecules fall into three different categories: nematic, chiral nematic, and smectic. Nematic Liquid Crystal Phase The simplest liquid crystal phase is called the nematic phase (N). It is characterized by a high degree of long range orientational order but no translational order. Molecules in a nematic phase spontaneously order with their (for calamitic molecules) long axes roughly parallel. Schematic diagram of a nematic liquid crystal A uniformly aligned nematic has a preferred direction, often described in terms of a unit vector called the director. More generally a bulk nematic will contain domains. The orientation of the director is constant in each domain but is different in different domains. Viewed under a polarizing microscope the defect regions linking these domains appear as dark threads Chiral Nematic Liquid Crystal Phase Chiral molecules can also form nematic phases called chiral nematic (or cholesteric) phases (N*). This phase shows nematic ordering but the preferred direction rotates throughout the sample. The axis of this rotation is normal to the director. An example of this is shown in Fig (b). The distance over which the director rotates by 360 is called the chiral pitch and is generally of the order of hundreds of nanometres, the wavelength of visible light. A non-chiral nematic phase can be thought of as a chiral nematic with an infinite pitch. Fig (b). Smectic Liquid Crystal Phases Smectic phases have further degrees of order compared to the nematic phase. In the simplest smectic phase, the smectic-A (SmA) phase, the molecules order into layers, with the layer normal parallel to the director. Within the layers, liquid like structure remains, as shown in Fig. 1.3. Closely related to the SmA phase is the smectic-C (SmC) phase. Here the molecules form a layer structure but the long axes of the molecules, and hence the director, lies at an angle to the layer normal, as shown in Fig. 1.4. There are many other smectic phases which have long range order within the layers Smectic phases can also be formed by chiral molecules, leading to chiral smectic phases. Discotic Liquid Crystal Phases Liquid crystal phases formed by discotic molecules fall into three different categories: discotic nematic, discotic chiral nematic, and columnar. The discotic nematic is similar in structure to the calamitic nematic, although in this case the short axes of the molecules tend to lie parallel. The same holds for the discotic chiral nematic phases. Columnar phases are the discotic equivalent of the smectic phase. Here the molecules form columns. In the simplest case the short axes of the molecules lie parallel to the axis of the column and the columns are randomly distributed in space. More complicated discotic phases exist, where the short molecular axes lie at an angle to the column and translational order exists between the columns, analogous to the more complicated smectic phases. Other Thermotropic Phases Most of the phases exhibited by low molecular mass liquid crystals are described above. Recently however there has been much interest in the so-called `banana phases formed by bent-core molecules Some of these phases are chiral although the molecules forming them are achiral. Some high molecular mass polymers, liquid crystalline polymers (LCP), can also form liquid crystal phases. These fall into two categories depending on where the mesogenic part of the molecule is located. If the mesogenic unit is contained within the main polymer chain then it is termed a main chain liquid crystal polymer (MCLCP). These fall into two categories depending on where the mesogenic part of the molecule is located. If the mesogenic unit is contained within the main polymer chain then it is termed a main chain liquid crystal polymer (MCLCP). Lyotropic Liquid Crystal Phases Lyotropic liquid crystal phases are formed by amphiphilic molecules. These often consist of a polar head group attached to one or more non-polar chains and are often known as surfactants (surface active agents). A schematic is shown in Fig. 1.5. When these are dissolved in an appropriate solvent they self-assemble so the polar (hydrophilic) heads protect the non-polar (hydrophobic) tails. These structures are known as micelles. At low surfactant concentrations these are roughly spherical, as shown in Fig. 1.6. As the surfactant Concentration increases then other phases are formed. These include the hexagonal phase where the amphiphiles form cylinders that pack in a hexagonal array and the lamellar phase where the amphiphiles form a bilayer structure. Structure-Property Relationships in Liquid Crystals Despite this there exists only a poor understanding of how changes in molecular structure affect material properties. For liquid crystals this is complicated by several factors. Firstly, liquid crystal phases are formed by materials from the whole spectrum of chemical classes: organic, organometallic, and biological molecules can all form liquid crystal phases. Secondly, mesogenic molecules are generally quite large. A typical low mass mesogen will have from about 40-100 atoms. For liquid crystalline polymers and dendrimers this can be closer to a few thousand atoms. Liquid crystals tend to be flexible. This inhibits crystallization, preventing the direct transition from an isotropic liquid to a crystalline solid. It also leads to a large degree of conformational freedom, so properties are generally determined by more than just the equilibrium structure. Finally liquid crystal molecules often contain disparate parts (such as alkyl and perfluoroalkyl chains) that can have a large effect on the phase behaviour. Investigation of these factors by experimental or theoretical means should hopefully lead to a better understanding of structure-property relationships in liquid crystals. In principle the relationship between molecular structure and macroscopic properties can be investigated through the synthesis of series of similar mesogenic compounds. This however can be time consuming and may involve many difficult and expensive syntheses. Thus, the ability to determine the properties of a molecular structure before synthesis would be desirable. It is here that simulations can play an important role. Simulations on general molecular models can be used to find features that can lead to a particular property or phase. Atomistic simulations can be used to determine material properties of a particular molecular structure. Chemical Properties of Liquid Crystals Liquid crystals can be classified into two main categories: thermotropic liquid crystals, And lyotropic liquid crystals. These two types of liquid crystals are distinguished by the mechanisms that drive their self-organization, but they are also similar in many ways. Thermotropic transactions occur in most liquid crystals, and they are defined by the fact that the transitions to the liquid crystalline state are induced thermally. That is, one can arrive at the Liquid crystalline state by raising the temperature of a solid and/or lowering the temperature of a Liquid. Thermotropic liquid crystals can be classified into two types: enantiotropic liquid crystals, Which can be changed into the liquid crystal state from either lowering the temperature of a Liquid or raising of the temperature of a solid, and monotropic liquid crystals, which can only be Changed into the liquid crystal state from either an increase in the temperature of a solid or a Decrease in the temperature of a liquid, but not both. In general, thermotropic mesophases occur Because of anisotropic dispersion forces between the molecules and because of packing Interactions. In contrast to thermotropic mesophases, lyotropic liquid crystal transitions occur with the Influence of solvents, not by a change in temperature. Lyotropic mesophases occur as a result of Solvent-induced aggregation of the constituent mesogens into micellar structures. Lyotropic mesogens are typically amphiphilic, meaning that they are composed of both lyophilic (solventattracting) And lyophobic (solvent-repelling) parts. This causes them to form into micellar structures in the presence of a solvent, since the lyophobic ends will stay together as the lyophilic ends extend outward toward the solution. As the concentration of the solution is increased and The solution is cooled, the micelles increase in size and eventually coalesce. This separates the newly formed liquid crystalline state from the solvent. A very large number of chemical compounds are known to exhibit one or several liquid crystalline phases. Despite significant differences in chemical composition, these molecules have some common features in chemical and physical properties. There are two types of thermotropic liquid crystals: discotics and rod-shaped molecules. Discotics are flat disc-like molecules consisting of a core of adjacent aromatic rings. This allows for two dimensional columnar ordering. Rod-shaped molecules have an elongated, anisotropic geometry which allows for preferential alignment along one spatial direction. The rod-like low molar mass (LMM) liquid crystals, such as 5CB shown in the following Diagram: require an extended conformation of the molecule which must be maintained through the rigidityand linearity of its constituents. That is, in order for a molecule to display the characteristics of a liquid crystal, it must be rigid and rod-shaped. This is accomplished by the interconnection of two rigid cyclic units. The interconnecting group should cause the resulting compound to have a linear planar conformation. Linking units containing multiple bonds such as -(CH=N)-, -N=N-, -(CH=CH)n-, -CH=N-N=CH-, etc. are used since they restrict the freedom of rotation. These groups can conjugate with phenylene rings, enhancing the anisotropic polarizability. This increases the molecular length and maintains the rigidity. Applications of Liquid Crystals Liquid crystal technology has had a major effect many areas of science and engineering, as well as device technology. Applications for this special kind of material are still being discovered and continue to provide effective solutions to many different problems. Liquid Crystal Displays The most common application of liquid crystal technology is liquid crystal displays (LCDs.) This Field has grown into a multi-billion dollar industry, and many significant scientific and Engineering discoveries have been made. Liquid Crystal Thermometers As demonstrated earlier, chiral nematic (cholesteric) liquid crystals reflect light with a wavelength equal to the pitch. Because the pitch is dependent upon temperature, the color reflected also is dependent upon temperature. Liquid crystals make it possible to accurately gauge temperature just by looking at the color of the thermometer. By mixing different compounds, a device for practically any temperature range can be built. The mood ring, a popular novelty a few years ago, took advantage of the unique ability of the chiral nematic liquid crystal. More important and practical applications have been developed in such diverse areas as medicine and electronics. Special liquid crystal devices can be attached to the skin to show a map of temperatures. This is useful because often physical problems, such as tumors, have a different temperature than the surrounding tissue. Liquid crystal temperature sensors can also be used to find bad connections on a circuit board by detecting the cha racteristic higher temperature Optical Imaging An application of liquid crystals that is only now being explored is optical imaging and recording. In this technology, a liquid crystal cell is placed between two layers of photo conductor. Light is applied to the photoconductor, which increases the materials conductivity. This causes an electric field to develop in the liquid crystal corresponding to the Intensity of the light. The electric pattern can be transmitted by an electrode, which enables the Image to be recorded. This technology is still being developed and is one of the most promising Areas of liquid crystal research. Other Liquid Crystal Applications Liquid crystals have a multitude of other uses. They are used for nondestructive mechanical Testing of materials under stress. This technique is also used for the visualization of RF (radio frequency) waves in waveguides. They are used in medical applications where, for example, transient pressure transmitted by a walking foot on the ground is measured. Low molar mass (LMM) liquid crystals have applications including erasable optical disks, full color electronic slides for computer-aided drawing (CAD), and light modulators for color electronic imaging. As new properties and types of liquid crystals are investigated and researched, these materials are sure to gain increasing importance in industrial and scientific applications.

Moscow Communist Party

Boris Yeltsin proved to be an invincible leader. In the year 1985 he was made the first secretary to the Moscow Communist Party by President Mikhail Gorbachev. In the succeeding year he was elected to the Politburo. Subsequently, he was made the chairman of the Russian Supreme Soviet. In June 1991, he became the first elected president to Russia. His efforts at separating the Commonwealth of Independent States secured complete independence for Russia. Yeltsin faced several administrative setbacks and his economic and market reforms resulted in unrest and parliamentary disagreement.In November 1993 internal conflicts in parliament led to the seizure of the Russian Parliament Building. Subsequently, he emerged victorious and obtained greater presidential powers. Yeltsin faced serious health problems, he had to frequently shuffle cabinet members and he had to countenance the armed conflict in Chechnya. Nevertheless, he was re – elected in 1996 (Yeltsin, Boris (1931 – ). In Andromeda Encyclopedic Dictionary of World History). Boris Yeltsin strongly believed in the socialist ideology of the Communist Party of the Soviet Union or the CPSU.The party’s ideals of economic progress and social equality had made him to join the CPSU in the year 1961. Gradually Yeltsin gained in importance in the party and became a member of the construction department of the party’s Sverdlovsk Oblast committee in the year 1968. His rise in this department was remarkable and by the year 1975 he became the secretary of the committee. In 1976 Boris Yeltsin was appointed the secretary of the Sverdlovsk Oblast committee by Leonid Brezhnev. This position enabled him to procure membership of the CPSU’s Central Committee in 1981.He became an important leader in the CPSU and openly criticized perestroika or the political reforms introduced by Gorbachev. Later on Yeltsin followed Gorbachev’s policies, in order to reduce strained relations with the Western na tions (Colton). President Yeltsin’s foreign minister was Andry Kozyrev favored a Western alliance. However, the Russian foreign policy did not change. Boris Yeltsin encountered his western counterparts on several occasions during international summits. He maintained friendly relations with US presidents George H. W.Bush and Bill Clinton. He solicited US backing in international platforms such as the International Monetary Fund. Yeltsin was friendly with the European economic giants. Accordingly he maintained cordial relations with Helmut Kohl the Chancellor of Germany and leaders of France and the United Kingdom (Colton). Yeltsin was disinterested in NATO’s plans and he reluctantly acceded to its proposals to admit former non – Soviet bloc countries. In the year 1999 the NATO waged a war against Yugoslavia. This measure resulted in strained relations with Russia.Subsequently, Yeltsin terminated all relations with NATO and this served to isolate Russia. However, Russia did not assist Yugoslavia to fight with NATO. Yugoslavia was compelled to agree to NATO’s proposals and had to accept foreign occupation of the Kosovo Province. Yeltsin ensured that Russia was included in the joint forces that occupied Kosovo. He made attempts to make an ally of China in Russia’s battle against the supremacy of NATO, further trade practices and mutual cooperation with China flourished in his era (Colton).The economic and market reforms implemented by Yeltsin were opposed by the parliament. In 1993 the free market reforms created internal conflicts and military intervention had to be resorted to, in order to control the situation. Yeltsin was successful in these military operations. During the period 1994 to 1996 the Chechnya crisis developed and Yeltsin’s response to it invited international criticism. Moreover, the parliament was dominated by communist members who opposed and disagreed with him.His power commenced to decline due to his i ll health and much of his authority was transferred to the parliament owing to the constitutional conflicts of 1998, which emerged due the serious financial crisis. Despite these setbacks, Yeltsin reclaimed his powers by dissolving the government four times in the period 1998 to 1999. In May 1999 the parliament made an abortive attempt to impeach him. Eventually, he submitted his resignation on the 31st of December 1999 and Vladimir Putin succeeded him (Yeltsin, Boris (1931 – ). In The Macmillan Encyclopedia).Boris Yeltsin had supported the Baltic States for independence. In order to achieve this he emphasized that there should be fundamental and radical reforms. Yeltsin relinquished his CPSU membership and contested in the presidential elections. He was elected president of the RSFSR or Russian Soviet Federative Socialist Republic. Yeltsin had always demanded autonomy for the member republics of the federal USSR. He also persuaded the Russian parliament to enact legislations to give the republic’s laws precedence over the laws of the Soviet parliament.The congress bestowed emergency powers upon Yeltsin, which permitted him to rule by decree. This made him a popular president. After the futile coup, in 1991, against President Gorbachev, Yeltsin condemned the acts of the usurpers and demanded his reinstatement (Yeltsin, Boris Nikolayevich (1931 – ). In The Hutchinson Unabridged Encyclopedia including Atlas). Yeltsin’s leadership capability was severely tested during the economic crisis and subsequent deterioration of conditions in Russia. In September 1993 a coup attempt was made against him by the leaders of parliament, which was defeated.The conservative political parties won the December elections and this unexpected victory forced Yeltsin to review his economic policies (Yeltsin, Boris Nikolayevich (1931 – ). In The Hutchinson Unabridged Encyclopedia including Atlas). Yeltsin was criticized for taking the military initiati ve in Chechnya. Although, a peace treaty was entered into with Chechnya in May 1997, the war did not stop. Yeltsin dissolved the entire cabinet in March 1998, which surprised both Russia and the Western nations. He also appointed the fuel and energy minister Sergei Kiriyenko to the post of the prime minister of Russia.The Kiriyenko led government faced a major economic crisis, because of the sudden devaluation of the ruble in 1998. In the month of August in the same year, Yeltsin dismissed both Kiriyenko and the government. Yeltsin tried to appoint Viktor Chernomyrdin as the prime minister, but the Duma, which was dominated by communist members, rejected Chernomyrdin’s candidature for prime minister. This compelled Yeltsin to nominate Yevgeni Primakov as the prime minister. Subsequently, in May 1999, Yeltsin dismissed Primakov and his government.Yeltsin took this decision following a debate, in the Duma, as to whether Primakov was to be allowed to continue or Sergei Stepashin was to be made the acting prime minister. He appointed Stepashin as the acting prime minister after impeaching Primakov. The Duma approved of Yeltsin’s actions and confirmed Stepashin as the prime minister. However, Yeltsin was criticized all over the world for his failure to resolve the crisis in Chechnya (Yeltsin, Boris Nikolayevich (1931 – ). In The Hutchinson Unabridged Encyclopedia including Atlas).Yeltsin tried to continue the process of reforms but the conservative members of parliament opposed his initiatives. In order to evaluate the public’s attitude towards him, a referendum was conducted in 1993 in which he received a significant number of the votes. This prompted him to propose a new Russian constitution (Hough). Incidents like the confrontation with the hard core conservatives, which resulted in the dissolution of parliament and an armed conflict in which the Moscow parliament building was shelled, rendered Yeltsin’s political position very powerful.However, there was growing opposition towards him and economic instability and the war in Chechnya made it very difficult for Yeltsin. He emerged victorious but his ill health prevented him from participating in active politics. Yeltsin used to take sudden decisions, which would cause a great deal of astonishment to everyone and a very telling instance is that of his resignation as president in the year 1999 (Yeltsin, Boris (Nikolayevich) (1 Feb 1931 –). In The Crystal Reference Encyclopedia).In March 1998, President Yeltsin dismissed the government which included two prominent leaders, namely the prime minister and pro free market activist, Viktor Chernomyrdin and Anatoly Chubais, the first deputy prime minister. This action surprised the West which tried to improve trade practices with Russia. The sudden sacking of the government created tremors in the West. At this juncture, Yeltsin issued a communique that Russia would continue with the process of reforming the economy. This resulted in widespread disapproval in Russia, because of the economic setbacks that had lasted for years.Consequently, Yeltsin attempted to pacify the West and to secure their confidence he appointed Sergei Kiriyenko as the acting prime minister, who was considered to be a committed reformist. The Duma accepted his candidature as acting prime minister in its third round of voting. Kiriyenko formed the youngest cabinet in Russia (Russian Federation. In The Hutchinson Unabridged Encyclopedia including Atlas). Boris Yeltsin brought about the dissolution of the USSR. Scholars acclaim the contributions of Yeltsin in establishing the post Soviet order in Russia.Historians have named four men as having wrought change in this context, namely, Nikita Krushchev, Leonid Brezhnev, Mikhail Gorbachev and Boris Yeltsin. These four men constitute the four pillars of modern decentralized Russian politics. Krushchev attempted to reform the age old centralized political system, Brezhnev tried to consolidate and then adopt it, Gorbachev endeavored to transform it into a social democracy and Yeltsin attempted to destroy the whole system and replace it with a new system (Brown). Works Cited Brown, Archie.Gorbachev, Yeltsin, and Putin: Political Leadership in Russia's Transition. ISBN 0870031864: Carnegie Endowment, 2001, p45. Colton, Timothy J. â€Å"Boris Yeltsin . † Microsoft ® Student 2008 [DVD]. Redmond, WA: Microsoft Corporation, 2007, 2007. Hough, Jerry F. Democratization and revolution in the USSR, 1985-1991 . ISBN 0815737483, p405: Brookings Institution Press, 1997. Russian Federation. In The Hutchinson Unabridged Encyclopedia including Atlas. 2005. 7 November 2007 . Yeltsin, Boris (1931 – ).In Andromeda Encyclopedic Dictionary of World History. 2001. 7 November 2007 . Yeltsin, Boris (1931 – ). In The Macmillan Encyclopedia. 2003. 7 November 2007 . Yeltsin, Boris (Nikolayevich) (1 Feb 1931 –). In The Crystal Reference Encyclopedia . 2005. 7 November 2007 . Yeltsin, Boris Nikolayevich (1931 – ). In The Hutchinson Unabridged Encyclopedia including Atlas. 2005. 7 November 2007 .

14. . . . . . Should Illegal Immigrants Be Allowed To Stay

14 Should illegal immigrants be allowed to stay in the U.S By Tyrese Ellis English Mr.wilson March 14, 2017 Yes, Why? The united states is a country of free rights. Not being born in the UnitedStates shouldent mean they arent allowed to live in a country of equal right and freedom of speech. Illegal families have the chance of opportunity and a chance in life. Why do families travel all the way from thier country to the U.S? Foreign families travel all the way to the United States because the United states has oppurtunity, Whats oppurtunity ? A set of circumstances that makes it possible to do something. Getting the chance to achieve a goal and to get to†¦show more content†¦Gaining legal status would likely mean three things for people now living in the US illegally†¦ First, they would no longer be subject to deportation solely because they’re in the country illegally, as long as they are law abiding in other ways. Second, they would be authorized to work. Third, they would have the ability to travel in and out of the United States. At least 60 percent of the illegal population has been in the US for more than 10 years†¦ and are unable to return to their home countries to visit family or for other reasons†¦ [A] path to citizenship for illegal immigrants, means that as naturalized citizens, they would be eligible to receive government benefits, such as unemployment insurance and Social Security. They could vote. And they would be eligible for special immigration privileges, such as being able to bring family members into the country. If they commit a crime, they can t be deported. Republicans have long been conflicted over U.S. immigration policy. On the one hand, consistent majorities of Republicans favor providing a path to legal status for people in the U.S. illegally. Yet most Republicans also worry that granting legal status to undocumented immigrants would amount to a tacit reward for illegal behavior. 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UNC Charlotte Acceptance Rate, SAT/ACT Scores, GPA

The University of North Carolina at Charlotte is a public research university with an acceptance rate of 67%. Located in North Carolinas largest city, UNC Charlotte has grown from a small teachers college to a large comprehensive university since its founding in 1946. The university is comprised of seven colleges, and undergraduates can choose from  over 78 bachelors degree programs. Preprofessional fields in business and health are among the most popular with undergraduates. On the athletic front, the Charlotte 49ers compete in the NCAA Division I Conference USA (C-USA). Considering applying to UNC Charlotte? Here are the admissions statistics you should know, including average SAT/ACT scores and GPAs of admitted students. Acceptance Rate During the 2017-18 admissions cycle, UNC Charlotte had an acceptance rate of 67%. This means that for every 100 students who applied, 67 students were admitted, making UNC Charlottes admissions process somewhat competitive. Admissions Statistics (2017-18) Number of Applicants 17,119 Percent Admitted 67% Percent Admitted Who Enrolled (Yield) 32% SAT Scores and Requirements The University of North Carolina at Charlotte requires that all applicants submit either SAT or ACT scores. During the 2017-18 admissions cycle, 65% of admitted students submitted SAT scores. SAT Range (Admitted Students) Section 25th Percentile 75h Percentile ERW 560 630 Math 560 640 ERW=Evidence-Based Reading and Writing This admissions data tells us that most of UNC Charlottes admitted students fall within the top 35% nationally on the SAT. For the evidence-based reading and writing section, 50% of students admitted to UNC Charlotte scored between 560 and 630, while 25% scored below 560 and 25% scored above 630. On the math section, 50% of admitted students scored between 560 and 640, while 25% scored below 560 and 25% scored above 640. Applicants with a composite SAT score of 1270 or greater will have particularly competitive chances at the University of North Carolina at Charlotte. Requirements UNC Charlotte does not require the SAT writing section or SAT Subject tests. Note that UNCC participates in the scorechoice program, which means that the admissions office will consider your highest score from each individual section across all SAT test dates. ACT Scores and Requirements UNC Charlotte requires that all applicants submit either SAT or ACT scores. During the 2017-18 admissions cycle, 66% of admitted students submitted ACT scores. ACT Range (Admitted Students) Section 25th Percentile 75th Percentile English 20 25 Math 21 26 Composite 21 26 This admissions data tells us that most of UNC Charlottes admitted students fall within the top 42% nationally on the ACT. The middle 50% of students admitted to UNCC received a composite ACT score between 21 and 26, while 25% scored above 26 and 25% scored below 21. Requirements Note that UNC Charlotte does not superscore ACT results; your highest composite ACT score will be considered. UNC Charlotte does not require the ACT writing section. GPA In 2018, the middle 50% of UNC Charlottes incoming class had high school GPAs between 3.2 and 3.7. 25% had a GPA above 3.7, and 25% had a GPA below 3.2.These results suggest that most successful applicants to the University of North Carolina at Charlotte have primarily B grades. Self-Reported GPA/SAT/ACT Graph University of North Carolina at Charlotte Applicants Self-Reported GPA/SAT/ACT Graph. Data courtesy of Cappex. The admissions data in the graph is self-reported by applicants to the University of North Carolina at Charlotte. GPAs are unweighted. Find out how you compare to accepted students, see the real-time graph, and calculate your chances of getting in  with a free Cappex account. Admissions Chances The University of North Carolina Charlotte has moderately selectively admissions. Admitted students tend to have grades and standardized test scores that are a little above average. Strong grades in challenging classes and solid SAT/ACT scores will be the most important part of your application. The university does not require an essay or letters or recommendation. Note that Art, Architecture, and Music have additional application requirements such as portfolios and auditions. In the graph above, the blue and green dots represent accepted students. As the data points show, most admitted students had high school grade point averages of B or higher, SAT scores of 1000 or higher (ERWM), and ACT composite scores of 20 or better. Your chances are best if your numbers are a little above this range. Note that there are a few red dots (rejected students) and yellow dots (waitlisted students) mixed in with the green and blue of the graph. This is because the UNC Charlotte admissions process isnt based entirely on grades and test scores. Applicants must have completed the required number of college preparatory courses (four units of English, four units of math, two units of social studies, three units of science, and two units of the same foreign language). The admissions folks will also be looking for students who continue to take the most challenging coursework during their senior year, and successful applicants often complete additional math, science, and language courses. All admissions data has been sourced from the National Center for Education Statistics and the University of North Carolina at Charlotte Undergraduate Admissions Office.