{"id":993,"date":"2009-03-13T03:25:38","date_gmt":"2009-03-13T03:25:38","guid":{"rendered":"http:\/\/www.fyysika.ee\/wordpress\/?p=993"},"modified":"2009-03-13T03:25:38","modified_gmt":"2009-03-13T03:25:38","slug":"","status":"publish","type":"post","link":"https:\/\/www.fyysika.ee\/?p=993","title":{"rendered":"Naatrium muutub k\u00f5rgel r\u00f5hul l\u00e4bipaistvaks"},"content":{"rendered":"<p>\n<strong>K&otilde;rgel r&otilde;hul kaotab naatrium metallilised omadused ja saab l&auml;bin&auml;htavaks<\/strong><\/p>\n<p>Hariliku toatemperatuuri ja &otilde;hur&otilde;hu juures on naatrium pehme ja l&auml;ikiv metall. Ehk m&otilde;ni lugeja m&auml;letab kooli keemiaklassist klaaspurki, kus &otilde;likihi all lebas pehme metallit&uuml;kk, mis &otilde;hu k&auml;es kiiresti tuhmiks t&otilde;mbus ja veega kokku puutudes koguni plahvatada v&otilde;is. Vastne eksperiment n&auml;itab, et k&otilde;rgetel r&otilde;hkudel k&auml;itub see metall hoopis  eriskummaliselt. Katses kasutatud r&otilde;hk<\/p>\n<table width=\"200\" cellspacing=\"1\" cellpadding=\"1\" border=\"0\" align=\"right\" summary=\"\">\n<tbody>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" height=\"127\" width=\"252\" alt=\"\" src=\"http:\/\/www.fyysika.ee\/pildid\/130309.jpg\" \/><\/td>\n<\/tr>\n<tr>\n<td><em>L&auml;bipaistev (199GPa) ja l&auml;bipaistmatu (156GPa) naatrium. Pilt: Nature<\/em><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>k&uuml;&uuml;ndis &uuml;le 200 gigapaskali (&uuml;ks gigapaskal on r&otilde;hk, mis valitseks 100 kilomeetri s&uuml;gavusel vee all, kui niisugune paik leiduks) ja naatrium muutus seejuures elektriisolaatoriks ning mis veelgi kummastavam &#8211; n&auml;htavale valgusele l&auml;bipaistvaks. Teoreetiliselt p&otilde;hjendatakse seda ioonkristallile sarnase struktuuri tekkimisega, kus anioonide rolli m&auml;ngivad lokaliseerunud elektronipaarid. Erinevaid faasi&uuml;leminekuid r&otilde;hkudel 100-200 GPa uuriti r&ouml;ntgrndifraktsiooni ja Raman-spektroskoopia abil. Esimene meetod v&otilde;imaldab aine kristallstruktuuri tuvastada selle p&otilde;hjal, kuidas jaguneb temale langev kindla lainepikkusega r&ouml;ntgenkiirte kimp ruumis p&auml;rast hajumist ainel. Raman-spektroskoopia v&otilde;imaldab leida aine koostisosakeste v&otilde;nkumiste ja p&ouml;&ouml;rlemistega seotud energiaid ja seel&auml;bi saada aimu aine siseehitusest. Niisugune uus teave aitab tulevikus koostada paremaid mudeleid veel katsetamata ainete omaduste kirjeldamiseks k&otilde;rgetel r&otilde;hkudel.<\/p>\n<p>Allikas: <a href=\"http:\/\/www.nature.com\/nature\/journal\/v458\/n7235\/abs\/nature07786.html\"><em>Nature<\/em> <\/a><strong><a href=\"http:\/\/www.nature.com\/nature\/journal\/v458\/n7235\/abs\/nature07786.html\">458<\/a>: <\/strong><em>Transparent dense sodium<\/p>\n<p><\/em>Toimetas Erik Randla<em><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>K&otilde;rgel r&otilde;hul kaotab naatrium metallilised omadused ja saab l&auml;bin&auml;htavaks Hariliku toatemperatuuri ja &otilde;hur&otilde;hu juures on naatrium pehme ja l&auml;ikiv metall. Ehk m&otilde;ni lugeja m&auml;letab kooli keemiaklassist klaaspurki, kus &otilde;likihi all lebas pehme metallit&uuml;kk, mis &otilde;hu k&auml;es kiiresti tuhmiks t&otilde;mbus ja veega kokku puutudes koguni plahvatada v&otilde;is. Vastne eksperiment n&auml;itab, et k&otilde;rgetel r&otilde;hkudel k&auml;itub see metall [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[16],"tags":[],"class_list":{"0":"post-993","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-teadusuudis","7":"entry"},"_links":{"self":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/993","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=993"}],"version-history":[{"count":0,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/993\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=993"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=993"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=993"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}