Friday, March 20, 2020
Mental Health Service Users In Higher Education Social Work Essays
Mental Health Service Users In Higher Education Social Work Essays Mental Health Service Users In Higher Education Social Work Essay Mental Health Service Users In Higher Education Social Work Essay Following legion policy directives from the Department of Health, the inclusion of service users in the preparation of wellness professionals has become compulsory. Service user groups are peculiarly active in mental wellness preparation and there are several enterprises that have been implemented within the UK to ease their engagement in higher instruction bringing. This paper undertakes a critical reappraisal of the placement of mental wellness service users in developing programmes within a diverse scope of subjects, and categorises them into three countries: understanding the new linguistic communication, barriers and benefits, and the positions and readying of service users for functions within higher instruction. While there are promoting developments within this country, there is besides a demand to develop consistence in readying and development of these enterprises to counter the barriers that may authors rise. In 1999 the National Service model for Mental Health ( Department of Health, 1999 ) established that service users ( SU ) and carers must go involved in all facets of the preparation for wellness attention professionals. Since so, farther paperss such as the Health and Social Care Act ( 2001 ) ; Commissioning a Service User Led NHS ( Department of Health, ) and the White Paper Our Health, Our Care, Our Say ( Department of Health, 2005b ) , every bit good as enterprises lead by The Health Care Commission ( 2005 ) have contributed to locate service users engagement in higher instruction ( HE ) as a precedence on the docket of mental wellness policies. Such enterprises straight challenge traditional theoretical accounts of attention where professionals were seen as the experts in mental wellness jobs while service users were a passive receiver of attention ( Foucault, 1980 ) . Mental wellness is today conceptualised as -a continuum, on which all mental wellness provinces are featured. To ease the execution of authorities policies workforce alliances and educational establishments have developed farther guidelines for the engagement of service users and carers in higher instruction. For illustration, the National Institute for Mental Health ( NIMHE ) adapted degrees of engagement developed by several writers ( Forrest, Risk, Masters, A ; Brown, 2000 ; Goss A ; Miller, 1995 ) to assist Workforce Development Confederations to scrutinize user and carer engagement in higher instruction. Additionally, Tew, Gell and Foster ( 2004 ) developed an appraisal model to be used for higher instruction establishments. The ladder of engagement considers that mental wellness service users could take part at different degrees runing from degree one ( no engagement ) to level five ( engagement in complete partnership ) . Professional and regulative organic structures have shown conformity with policies taking to new criterions of attention. For illustration, the Royal College of Psychiatrists made mandatary for trainees in psychopathology to have preparation from SUs ( Fadden, Shooter, A ; Holsgrove, 2005 ) ; the Chief Nursing Officer s Review of Mental Health Nursing ( Department of Health, 2006 ) established new nucleus competencies that have to be achieved through incorporating SUs within the nursing educational procedure and service users, and carers form portion of the revised standards for the Accreditation of Postgraduate Training Programs in Clinical Psychology ( BPS 2008 ) . Since the launch of all those policies, a overplus of illustrations and articles has emerged demoing how service users and carers have contributed to mental wellness and societal attention instruction at a scope of degrees and through the UK geographics. For illustration, in nursing ( Frisby, 2001 ; Langdon, Barnes, Haslehurst, Rimmer, A ; Turton, 2003 ) ; societal work ( Branfield, 2009 ; Levin, 2004 ) ; clinical psychological science ( Cooke A ; Hayward, 2010 ; Harper, Goodbody, A ; Steen, 2005 ) and medical preparation ( Fadden et al. , 2005 ; Wykurz A ; Kelly, 2002 ) . Such grounds surely highlights the development of user-involvement in HE, and illustrations of good pattern have been disseminated. However there is small effort to synthesize this literature peculiarly with mention to HE bringing. Taking all the above into history, a critical reappraisal of the literature was felt necessary at this phase. The chief purpose was to place emergent subjects and concerns shared by writers when using constabularies of users involvement in higher instruction into pattern and to place countries of farther work in pattern and research. The literature reappraisal: hunt scheme The hunt standards were refined to literature published since 1999 in line with the National Service Framework for mental wellness. Several on-line databases were searched: AMED, BNI, CINAHL, EMBASE, Health Business Elite, MEDLINE, PsychArticles, PsycInfo, ScienceDirect, and Web of Knowledge. Using a synonym finder and free text hunts, hunt footings were expanded to include mental wellness, service user, engagement, engagement, higher instruction, college, university, instruction, and pupil. In entire, over two 100 articles were retrieved and their mention lists hand- searched through to place farther relevant literature that may non hold appeared in the original database hunt. To spread out the hunt, writers of the most relevant articles were contacted, as were conference talkers and website decision makers in an attempt to supply inside informations of any current research they may be involved in. To set up relevance and to bring forth a literature reappraisal that was both extended but besides specific to our subject of involvement, we needed to specify the exact parametric quantities that we were seeking for. This led us to set up some exclusion standards. One such exclusion was articles that addressed mental wellness service users engagement in research undertakings. Many articles documented how service users were being recruited as participants in university research undertakings. However, these illustrations of SU engagement were non direct instruction and were non specifically aligned to education bringing. Our focal point was on how HE establishments involved service users in categories, talks, and as established members of staff in their instruction programmes. We besides chose to exclude any mention to service users being involved in instruction unless it was specifically higher instruction. Much of the stuff addressed how service users could take part in the prepara tion of health care professionals, but within independently organised workshops. We felt that that utilizing these exclusion standards would non merely supply a streamlined hunt scheme relevant to our research subject, but would besides let us to detect how establishments were following with the aforesaid authorities statute law to include service users in the bringing of higher instruction. Searching the literature in this manner was conducted on the footing of seeking to reply several inquiries. The first indispensable question lies in finding the current state of affairs of engagement of mental wellness SUs in HE. A demand besides exists to set up the chief issues that emerge with seeking to use current policies on mental wellness SUs and developing wellness professionals. Finally the cardinal question demands what we can larn from the grounds and what future developments are possible. Consequences: general observations Maping the literature resulted in a principal of surveies that spanned several subjects. From the articles that met our inclusion criteria the following capable countries from which they emerged were identified: Nursing = 53 articles Social Work = 26 Inter-professional = 22 Medical = 16 Psychiatry = 7A Psychology = 2 In measuring the attack of these surveies, we identified the undermentioned dislocation: Involvement suggestions = 17 ( e.g. appraisal ) Involvement ratings = 22 Case study = 40 Contemplations = 15 ( e.g. interviews, SU experiences ) Literature reappraisal = 8 Quantitative study = 5 Other = 19 ( e.g. Conference proceedings, web site, workshop ) Three systematic reappraisals were identified. Repper A ; Breeze ( Repper A ; Breeze, 2004 ) reviewed the literature on user and carer engagement in the preparation and instruction of mental wellness attention workers. They found that the bulk of documents selected for their reappraisal provided descriptions of consumer engagement undertakings with accent on the procedure of affecting users and callings instead than looking at the consequence that this engagement produced in pupils. Merely seven documents reported the result of consumer engagement in training/education and none examined the consequence of such instruction on pattern. Traveling more specifically in to mental wellness pattern for nursing pupils, Gray et Al. ( 2010 ) found that several writers ( e.g. Branfield, 2009 ; Speers, 2008 ) recommended the development of protocols to supply construction when affecting users in these activities. Wykurtz and Kelly ( 2002 ) completed a systematic reappraisal of publications from 1970 to 2001 discoursing the function of patients as active instructors in medical instruction. They identified 23 articles being merely one of these articles related to mental wellness, and the lone one co-authored by a health professional or patient ( Butterworth A ; Livingston, 1999 ) . They contributed to the grounds of positive benefits in users engagement in HE. Such reappraisals provide a utile penetration into bing work. Upon farther examination, we besides identified emergent subjects that the retrieved articles demonstrated. These will each be discussed and are: Understanding the new linguistic communication: issues originating from the usage of the new vocabulary, definition of specific footings, such as users and carers Barriers and Benefits: researching the single and institutional concerns built-in in the constitution and care of SU engagement. Service users readying and positions of engagement in HE bringing: turn toing the nature of preparation and designation of larning demands for SUs and carers. Understanding the new linguistic communication The inter-changeability and fluctuation of the nomenclature used in the articles was a most outstanding observation. In footings of specifying higher instruction, the information retrieved covered a scope of wellness professionals and subjects: medicine/psychiatry, nursing, occupational therapy, societal work, psychological science, graduate mental wellness workers, other professionals/programs ( e.g. certification in mental wellness work ) . Equally varied was the terminology applied to SUs and carers. Mental wellness SUs and carers are both different by definition and demands. However sometimes these footings appear in the literature as one sole entity and used inclusively. Traditionally, wellness professionals have given different names to the population they attend following the assorted theoretical theoretical accounts used as model. Doctors and nurses refer to the people they see for appraisal and intervention as patients while professionals from societal work A ; psychology specify them as clients and the footings users and/or, consumers are normally used from a managerial position. The term service user was adapted from societal policy by societal work in the early 1990s and it has become widely used across the UK by wellness and societal attention professions ( Anghel A ; Ramon, 2009 ) . Peoples widely accept these differences in vocabulary ( McGuire-Snieckus, McCabe, A ; Priebe, 2003 ) and suit to them. Service user administrations are besides lending to the field giving their ain definitions. They advocated that a service user should ever be self-identifying and seen as a individual foremost ( Determining our Lifes, 2003 ) and they have suggested to utilize the term citizen stakeholders ( Advocacy in Action, 2006 ) or to use footings such as resistant and survivors ( Distress Awareness Training Agency Website, 2010 ) All these incompatibilities sing the more appropriate nomenclature to be used were reflected in the literature and had been highlighted by writers ( Gray et al. , 2010 ; Rees, Knight, A ; Wilkinson, 2007 ; Simpson, Barkham, Gilbody, A ; House, 2003 ) . Some of them have adopted the definition proposed by Cooper A ; Spencer-Dawe ( 2006 ) in that that a service user is a individual who is ( or has been ) having any type of wellness or societal attention service. This definition has been seen a impersonal one ( Simpson et al. 2003 ) . Others ( Anghel A ; Ramon, 2009 ; Middleton, Stanton, A ; Renouf, 2004 ) proposed footings such as consultant , consumer adviser and/ or mental wellness consumer adviser to designate mental wellness service users as this would be more in harmony with the function they presently play. Others disagreed with this new nomenclature ( Moss, Boath, Buckley, A ; Colgan, 2009 ) as they have found in their surveies that participants would prefer the term s ervice user while others found that this may be inappropriate and considered violative ( Humphreys, 2005 ; Tyler, 2006 ) . Furthermore, understanding the new linguistic communication applies in the other way, this being service users going accustomed to the linguistic communication within academe. Many writers assert that the nature of academic argument and attach toing slang can efficaciously except service users and carers, and hence consequence in them experiencing intimidated and frustrated ( Basset, Campbell, A ; Anderson, 2006 ; Essen et al. , 2009 ; Scots Voices, 2008 ; Tew et al. , 2004 ) . Such sentiments lead suitably to the wider consideration of barriers to serve user integrating in higher instruction. Barriers and benefits Many articles approached the barriers to and benefits of SU engagement in both single and institutional contexts. On institutional degrees, several writers raised the high spot that the hierarchal civilization and constructions present within the HE establishments do non ease effectual coaction between faculty members and SUs. More specifically there was an inexplicit political orientation held that HE itself was a beginning of subjugation and exclusion that maintains bing inequalities in power dealingss and hierarchies ( Boxall, Carson, A ; Docherty, 2004 ; Hanley, 2005 ) . Other articles asserted that some faculty members used their cognition and expertness to project a sense of high quality over service users and carers and hence devaluate their engagement and sentiments ( Basset et al. , 2006 ; Branfield, Beresford, A ; Levin, 2007 ; Dogra, Anderson, Edwards, A ; Cavendish, 2008 ; Forbat, 2006 ; Tait A ; Lester, 2005 ) . Rees et Al. ( 2007 ) province that frequently service users and carers are non seen as holding a legitimate portion to play in instruction and preparation. In peculiar with regard to appraisal, the Social Care Institute for Excellence ( 2009 ) make the point that some faculty members believe that the appraisal of pupils is the exclusive state of them and disregard any added value that could be gained from the engagement of service users or carers. Such positions convey a damning indictment upon the purposes to make meaningful engagement, and are so barriers of an abstract and cloudy nature. However, on a more single degree, there are some practical and logistical concerns that besides serve to impede instead than advance engagement. Concerns such as payment of disbursals and concerns held by SUs that this may impact benefits, ( Basset et al. , 2006 ; Branfield et al. , 2007 ; Brown A ; Young, 2008 ) . Entree to installations, and a perceived tokenistic usage of SUs besides contrib ute to the structural and hierarchal hindrances outlined earlier. Felton and Stickley ( 2004 ) interviewed five mental wellness lectors to determine their positions of affecting service users in learning the undergraduate mental wellness nursing programme. Whilst four out of the five lectors by and large considered user engagement to be a good thing their subsequent parts suggested ambiguities. Although demoing consciousness of possible disadvantages of user engagement in higher instruction, respondents were non ever clear about the advantages. Furthermore, lectors did non desire the service users to go professionalised ; they wanted their function as patients maintained as this was perceived as more utile for engagement in the programme. Another sensed disadvantage for the users going professionalised was an eroding of their ain functions into that of glorified markers . In add-on to practical concerns that can straight impact persons, such issues arise in organizational factors. Other barriers raised in the literature concern the deficiency of substructure within SU administrations to get by with demand. The literature asserts that the engagement of service users and carers in the educational procedure equates to clip and resource ingestion when these trade goods are already committed ( Basset et al. , 2006 ; Edwards, 2003 ) . While HE administrations may non keep such disadvantages, it is argued that an built-in bias towards service users still abounds every bit, such as being disablement, undependability, being unpredictable or even unsafe ( Felton A ; Stickley 2004 ; Basset et Al. 2006 ; Branfield et Al. 2007 ; ( Haffling A ; Hakansson, 2008 ) ( Happell A ; Roper, 2009 ) ) . In malice of the aforesaid barriers identified in the literature, some articles besides featured the benefits of SU engagement in HE bringing. For pupils of classs in which Sessionss were delivered by SUs, the chance to reflect upon thought arousing feedback from SUs increased their assurance, motive and encouragement to farther heighten their pattern ( Bideau, Guerne, Bianchi, A ; Huber, 2006 ; Duxbury A ; Ramsdale, 2007 ) . Indeed, the wider issue of larning through brooding feedback is strongly supported whether the feedback was positive or negative. Evidence showed that positive and constructive feedback from service users and carers welcomed it and believed it was an of import portion of pupils acquisition procedures, while less than positive feedback sparked de-motivation ( Bailey, 2005 ) . Bailey besides reported that all service users found themselves sympathizing with the individual who was the focal point of the pupils appraisal and commented that they had felt empowere d and as a consequence of working with other service users had made new societal contacts. Other surveies reported that both pupils and user/carer participants found the experience positive. The pupils felt that listening to the user and carer position had facilitated a greater apprehension. The pupils felt privileged to hear the carer s narrative, happening the experience traveling, enlightening and informative ( Turner et al. , 2000 ) . Wood and Wilson-Barnett ( 1999 ) evaluated the consequence of user engagement on pupil larning utilizing a comparing research design. The findings showed pronounced differences between pupils who were and were non exposed to users. Students who had earlier exposure to user engagement showed more empathy and used less professional slang and a more individualized attack. They conclude that affecting service users earlier instead than subsequently in a programme may be more effectual in footings of act uponing larning If having negative feedback, pupils unsurprisingly became doubting about the whole procedure which impinged on their perceptual experience of the value of affecting service users and carers in their appraisal ( Rees et al. , 2007 ; Speers, 2008 ; Stickley et al. , 2010 ) besides made the observation that some of the pupils in their survey believed that the feedback from SUs was excessively glowing and lacked constructive unfavorable judgment. In seeking farther positions of SUs, many surveies shared the determination that they valued most extremely the humanistic accomplishments of pupils and led to increased power sharing , but this was limited within the university environment. These surveies besides highlighted that maintaining the impulse traveling for user engagement in professional instruction requires changeless high degrees of energy and committedness ( Masters et al. , 2002 ) which can be translated as added value ( Barnes, Carpenter, A ; Bailey, 2000 ) . Barnes et al. us ed a instance survey methodological analysis to measure a post-graduate programme of inter-professional instruction in community mental wellness. This paper besides described the development of a questionnaire to measure added value for SUs which could be attributed to the programme. The results that SUs prioritised were: pupils showing apprehension, and non merely seeking to work out jobs or push people into services ; handling service users with regard, non as labels ; professionals developing their capacity to be human ; pupils holding cognition about services, including protagonism services and service user groups ; and being able to supply information about how to affect service users in measuring their demands. Overall, this survey found that, whilst users parts were valued, they were non given the same acceptance by the programme participants as parts from senior faculty members from the field of psychopathology and psychological science. Masters et Al. ( 2002 ) focused on the rating of a scheme papers and its execution, from the position of all the stakeholders. Data was collected by two questionnaires, compiled for the intent. The service users found benefits in the acquisition of new accomplishments, increased assurance and a echt feeling of authorization. The issue of group rank besides straddles barriers and benefits of SU engagement in HE bringing. While there are clear benefits to pupils in footings of larning experience and great chances for common regard and partnerships between the HE and SU communities, there are besides troubles associated with keeping the positive differentiations between these groups to achieve meaningful engagement and pedagogical equilibrium. Indeed, several commentaries make the point that as service users and carers become used to the educational environment and learn to get by with the civilization so they are no longer genuinely representative of the service carer group ( Ahuja A ; Williams, 2005 ; Felton A ; Stickley, 2004 ; McGarry A ; Thom, 2004 ; Tait A ; Lester, 2005 ) . Such issues are per se held within the readying and preparation that SUs receive and besides deliver, which leads to the tierce of our subjects. Service users: readying and positions Few documents specified whether, or how, user or carer participants had been prepared for their educational function, nor how support was organised despite this being identified as of import by lectors ( Masters A ; Forrest, 2010 ; Turner et al. , 2000 ) and service users ( Curran, 1997 ) . Preparation tended to be informal such as a short telephone call ( Turner et al. , 2000 ) or a briefing before a instruction session to explicate the function of the participant ( Costello A ; Horne, 2001 ) . However, this limited or deficiency of information can ensue in user and carer participants experiencing unsure about their engagement, non understanding the intent, and experiencing that they lack expertness ( Spencer et al. , 2000 ) ; Turner et Al 2000 ; Masters et 2002 ) . Hanson and Mitchell ( 2001 ) follow a structured attack and maintain the focal point on the readying of mental wellness service users for engagement in instruction with the purpose to learn in the pre-registration of a mental wellness nursing class. A standard for engagement was users motive. The readying for mental wellness users, nevertheless, was more concerned with the techniques for the learning itself and a instruction and measuring faculty for nurses. One manner to guarantee, or at least assist equal readying is the formation of mention groups for the specific intent of SU engagement in higher instruction, for illustration by agencies of patient consultative groups through targeted audience ( Greenfield et al. , 2001 ) . Two documents discuss the procedure of organizing mention groups from bing consumer groups. Ingham ( 2001 ) describes the puting up of a mention group for the specific intent of supplying the user position to inform a new pre-registration class. Recruitment for the group was coordinated through the local wellness authorization and members were drawn from a broad spectrum of patient and voluntary service groups the mention group addressed the procedure of engagement, but in this instance, it identified land regulations for patient engagement with deductions for both the involved consumer and the educational administration. Sawley ( 2002 ) describes a series of meetings set up with consumers to specifically inform t he course of study content of kids s nursing classs. Recruitment for the group was made via a assortment of paths: a list of charities provided by the local community wellness council ; notices put up on kids s wards ; personal invitations sent to parents who nurses idea might be interested ; and by assorted media mercantile establishments. This enterprise did non merely act upon educational classs, but led to pattern development within Trusts and more effectual networking. The development of such groups to fix SUs for a function in HE bringing is surely a measure in the right way, but however can still fall quarry to the one-way street of faculty members urging and organizing these groups and puting their ain dockets. While this may sometimes be a starting point, a demand besides exists to guarantee that a bipartisan way leting SUs to put dockets excessively. This lies non merely in lending to content and bringing of instruction, but besides keeping facilitation of SUs and carers placing their ain acquisition demands and preparation development, as per recommendations by Advocacy in Action ( 2006b ) . Surveies identified from our hunts displayed grounds of such designation taking topographic point in footings of class results for wellness professionals. Two surveies reported consumers positions about what healthcare workers should be taught. All focused on service users positions about the preparation demands of mental wellness nurses ( Forrest et al. , 2000 ; Rudman, 1996 ) and the common determination was service users accent upon the humanistic qualities of lovingness and regard, and the importance of interpersonal accomplishments. Rudman ( 1996 ) collected informations from two mental wellness user groups ( 20 service users in entire ) by agencies of semi-structured group interviews. The users felt the indispensable qualities of mental wellness nursing to be: lovingness: maintaining caring despite socialization ; accessibility, immediateness and presence ; professional demeanor. Forrest et Al ( 2000 ) besides aimed to arouse user positions about the cognition, accomplishmen ts and attributes they considered that mental wellness nurses should possess but in add-on their survey explored schemes for user engagement in the on-going course of study design and bringing. Once once more, the SUs valued human qualities above professional accomplishments. A good nurse was described as person with common sense , heat and sensitiveness, as being nice and person who can be a friend. Many users in the survey felt that bing nursing classs are counterproductive with regard to the qualities they value due to the accent upon the professional qualities and the medical theoretical account. Decisions It is clear that SU engagement in HE bringing has generated many benefits for SUs, carers, pupils and faculty members likewise. Equally reviewing are the increased Numberss of surveies that seem to hold moved on from merely sing the benefits of SU engagement and are at the following degree of sing its impact, on many different degrees. There are besides, nevertheless, incompatibilities. These arise from rudimentss of nomenclature, through to the very execution of enterprises countrywide, which are at best described as patchy and unevenaÃâ Y ( Branfield, 2009 ; Speers, 2008 ) . One of the issues that is non ever evident in the literature and hence hard to thematise is extent of engagement of service users within different countries. Recommendations of pattern such as ladders of engagement ( Gutteridge A ; Dobbins, 2009 ; Tew et al. , 2004 ) are proposed, and some bear direct relevancy to HE bringing in footings of factoring learning activities, payment for talk rates and being involved in course of study determinations ( Forrest et al. , 2000 ) . These definitions of engagement are utile to define the extent to which SUs carers might be included, but this information could farther be augmented by the development of a clear cosmopolitan model for all parties. This is particularly relevant as the barriers identified in the literature continue to tilt towards residuary concerns of wage, tokenism, representation, enlisting and power instabilities, in add-on to the possibilities of the genuineness of a SU group being diminished as members become farther ens conced in HE procedures. Many policies have been introduced to regulate the way of a more service user/patient-led wellness service. However, in malice of the increased figure of those theoretical accounts of good pattern, the engagement of users and carers in higher instruction of wellness professionals still suggests a more ad hoc and local activity than one that follows national planning. It gives the feeling of organic structures being embarked in a helter-skelter endurance contest with the purpose to turn out conformity with authorities recommendations, flagging their undertaking as the most valued 1s, alternatively of following a brooding and organized mode of interpreting those policies into pattern. Furthermore, the Numberss of those illustrations are still a few in comparing with the extended figure of policies developed to that terminal. Service users engagement is non merely the modern focal point of the NHS it is a societal motion that deserves particular contemplation and considerations ( Crossl ey, 2002 ) . Repper and Breeze ( 2004 ) observed that accent was placed on interpersonal accomplishments of nurses with the deduction that other wellness fortes were conspicuous by their absence. It besides is still evident that a larger figure of surveies so far has emerged for the nursing literature in footings of SU inclusion within mental wellness nursing programmes. Other subjects need to increase their capacity to affect SUs. There is small uncertainty that research needs to go on into this country, with peculiar accent in SU and carers positions once they have established length of service of their associations with HE establishments.
Wednesday, March 4, 2020
Crystal Definition, Examples, and Common Types
Crystal Definition, Examples, and Common Types A crystal consists of matter that is formed from an ordered arrangement of atoms, molecules, or ions. The lattice that forms extends out in three-dimensions. Because there are repeated units, crystals have recognizable structures. Large crystals display flat regions (faces) and well-defined angles. Crystals with obvious flat faces are called euhedral crystals, while those lacking defined faces are called anhedral crystals. Crystals consisting of ordered arrays of atoms that arent always periodic are called quasicrystals. The word crystal comes from the Ancient Greek word krustallos, which means both rock crystal and ice. The scientific study of crystals is called crystallography. Examples of Crystals Examples of everyday materials you encounter as crystals are table salt (sodium chloride or halite crystals), sugar (sucrose), and snowflakes. Many gemstones are crystals, including quartz and diamond. There are also many materials that resemble crystals but are actually polycrystals. Polycrystals form when microscopic crystals fuse together to form a solid. These materials do not consist of ordered lattices. Examples of polycrystals include ice, many metal samples, and ceramics. Even less structure is displayed by amorphous solids, which have disordered internal structure. An example of an amorphous solid is glass, which may resemble a crystal when faceted, yet isnt one. Chemical Bonds in Crystals The types of chemical bonds formed between atoms or groups of atoms in crystals depend on their size and electronegativity. There are four categories of crystals as grouped by their bonding: Covalent Crystals - Atoms in covalent crystals are linked by covalent bonds. Pure nonmetals form covalent crystals (e.g., diamond) as do covalent compounds (e.g., zinc sulfide).Molecular Crystals - Entire molecules are bonded to each other in an organized manner. A good example is a sugar crystal, which contains sucrose molecules.Metallic Crystals - Metals often form metallic crystals, where some of the valence electrons are free to move throughout the lattice. Iron, for example, can form different metallic crystals.Ionic Crystals - Electrostatic forces form ionic bonds. A classic example is a halite or salt crystal. Crystal Lattices There are seven systems of crystal structures, which are also calledà latticesà or space lattices: Cubic or Isometric - This shape includes octahedrons and dodecahedrons as well as cubes.Tetragonal - These crystals form prisms and double pyramids. The structure is like a cubic crystal, except one axis is longer than the other.Orthorhombic - These are rhombic prisms and dipyramids that resemble tetragons but without square cross-sections.Hexagonal - Six-sided prisms with a hexagon cross section.Trigonal - These crystals have a 3-fold axis.Triclinic - Triclinic crystals tend not to be symmetrical.Monoclinic - These crystals resemble skewed tetragonal shapes. Lattices may have one lattice point per cell or more than one, yielding a total of 14 Bravais crystal lattice types. Bravais lattices, named for physicist and crystallographer Auguste Bravais, describe the three-dimensional array made by a set of discrete points. A substance may form more than one crystal lattice. For example, water can form hexagonal ice (such as snowflakes), cubic ice, and rhombohedral ice. It can also form amorphous ice. Carbon can form diamond (cubic lattice) and graphite (hexagonal lattice). How Crystals Form The process of forming a crystal is called crystallization. Crystallization commonly occurs when a solid crystal grows from a liquid or solution. As a hot solution cools or a saturated solution evaporates, particles draw close enough for chemical bonds to form. Crystals can also form from deposition directly from the gas phase. Liquid crystals possess particles oriented in an organized manner, like solid crystals, yet able to flow.
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