{"id":961,"date":"2009-10-03T09:42:06","date_gmt":"2009-10-03T08:42:06","guid":{"rendered":"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=961"},"modified":"2009-10-03T09:42:06","modified_gmt":"2009-10-03T08:42:06","slug":"pentavalent-nitrogen-and-boron","status":"publish","type":"post","link":"https:\/\/rzepa.net\/blog\/2009\/10\/03\/pentavalent-nitrogen-and-boron\/","title":{"rendered":"Pentavalent nitrogen and boron"},"content":{"rendered":"

The previous posts have seen how a molecule containing a hypervalent carbon atom can be designed by making a series of logical chemical connections. Another logical step is to investigate whether the adjacent atoms in the periodic table may exhibit similar effects (C2+<\/sup> \u2261 B+<\/sup> \u2261 N3+<\/sup> \u2261 Be \u2261 O4+<\/sup>). So here are reported some results (B3LYP\/6-311G(d,p) ) for boron, beryllium and nitrogen, for the general tetramethyl substituted system shown below<\/p>\n

\"Pentavalency
Pentavalency across a series<\/figcaption><\/figure>\n\n\n\n\n\n\n\n
X<\/td>\nCharge<\/td>\nX-C length, \u00c5<\/td>\n\u03c1(r) C-X<\/td>\nELF integration<\/td>\n\u03bd-Trampoline, cm-1<\/sup><\/td>\n\u03bd X-H, cm-1<\/sup><\/td>\nRepository<\/td>\n<\/tr>\n
N<\/td>\n2<\/td>\n1.616<\/td>\n.172<\/td>\n1.14<\/td>\n883<\/td>\n3417<\/td>\n10042\/to-2439<\/a><\/td>\n<\/tr>\n
C<\/td>\n1<\/td>\n1.580<\/td>\n.195<\/td>\n1.10<\/td>\n970<\/td>\n3291<\/td>\n10042\/to-2438<\/a><\/td>\n<\/tr>\n
B<\/td>\n0<\/td>\n1.649<\/td>\n.136<\/td>\n1.06<\/td>\n949<\/td>\n2746<\/td>\n10042\/to-2440<\/a><\/td>\n<\/tr>\n
Be<\/td>\n-1<\/td>\n1.817<\/td>\n.064<\/td>\n0.98<\/td>\n797<\/td>\n1887<\/td>\n10042\/to-2441<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

The systems H, C and B are stable in the sense that the C4v<\/sub>-symmetric calculated geometry has only positive calculated force constants (Be has a small negative frequency). All show bond critical points in the \u00a0X-C region (although these bonds are clearly \u00a0bent) and X-H region, and significant integrations for the X-C disynaptic basins in the \u00a0ELF analysis. The boron analogue is also of interest as being a neutral rather than a charged molecule, and therefore may be a worthy target for synthetic effort.<\/p>\n","protected":false},"excerpt":{"rendered":"

The previous posts have seen how a molecule containing a hypervalent carbon atom can be designed by making a series of logical chemical connections. Another logical step is to investigate whether the adjacent atoms in the periodic table may exhibit similar effects (C2+ \u2261 B+ \u2261 N3+ \u2261 Be \u2261 O4+). So here are reported […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10,11],"tags":[1230,1290,1467],"class_list":["post-961","post","type-post","status-publish","format-standard","hentry","category-hypervalency","category-interesting-chemistry","tag-hypervalency","tag-interesting-chemistry","tag-logical-chemical-connections"],"_links":{"self":[{"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/posts\/961","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/comments?post=961"}],"version-history":[{"count":0,"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/posts\/961\/revisions"}],"wp:attachment":[{"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/media?parent=961"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/categories?post=961"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rzepa.net\/blog\/wp-json\/wp\/v2\/tags?post=961"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}