PHOSPHORUS NA RAYUWA, AN HAIFE SHI A TSAKANIN TAURARI

Phosphorus ba shi da yawa a sararin duniya. A yanayin Rana akwai kusan atom 3 na phosphorus ga kowane atom miliyan 10 na hydrogen — kusan sau ɗari ƙasa da atom na sulfur. Duk da haka rayuwa ba za ta iya rayuwa ba tare da shi ba: phosphates suna da matuƙar muhimmanci ga DNA da RNA, masu ɗauke da bayanan gado, ga ATP da kuma ga phospholipids.

Yadda phosphorus ya samu ga sinadaran farko na rayuwa har yanzu tambaya ce a buɗe. Wata alama da marubutan suka ambata: an sami ƙwayoyi masu yawan phosphorus ba kamar yadda aka saba ba, saɓanin na sauran meteorites, a cikin samfuran da aka dawo da su daga asteroid Ryugu — alama cewa duwatsun sararin samaniya na iya kawo phosphorus ga Duniya tun tana sabuwa.

Gajeren jerin ƙwayoyin sinadarai

Masana ilimin taurari na rediyo sun gano fiye da ƙwayoyin sinadarai 40 da ke ɗauke da sulfur a sararin samaniya tsakanin taurari. Ga ƙwayoyin da ke haɗa phosphorus da carbon, jerin yana tsayawa a uku: CP, CCP da HCP, duka an same su a cikin lulluɓin tsofaffin taurari masu yawan carbon, tare da ganowa ɗaya da ba ta tabbata ba. Masana kimiyyar sinadarai sun gabatar da ƴan takara masu sarƙaƙiya da yawa, amma ba a san sosai yadda suke samuwa da yadda ake lalata su ba.

A cikin gajimaren gas masu yaɗuwa, phosphorus yana kasancewa mafi yawa a matsayin ion mai caji mai kyau, P⁺. Wani martani ɗaya ya yi kama da mai alƙawari musamman: P⁺ yana haɗuwa da acetylene (C₂H₂), wani ƙwayar carbon da aka saba gani. Aunawarsa ɗaya tilo ta samo asali daga 1989–1990, a zafin ɗaki, kuma rumbun bayanan sinadaran sararin samaniya (astrochemistry) kawai suna zaton sauri iri ɗaya a kowane zafi. A gefe guda, wani lissafi na 2012 ya yi hasashen sauri ƙasa da sau goma. Wani abu bai dace ba.

Ion sun haɗu da acetylene a SOLEIL

Matteo Michielan, Daniela Ascenzi (Jami’ar Trento, Italiya), Alexandre Zanchet (CSIC, Madrid) da abokan aikinsu a Faransa, Spain da Czechia sun koma ɗakin gwaji. A synchrotron na SOLEIL kusa da Paris, sun samar da ion na phosphorus ta hanyar fasa ƙwayoyin phosphorus trichloride da hasken ultraviolet, suna zaɓar kuzarin da kyau ta yadda ion da ke cikin yanayinsu mafi ƙasƙancin kuzari kawai aka samar — zaɓin da suka duba da wani martanin gwaji daban.

Sannan suka jagoranci ion ɗin ta cikin wani ɗaki na acetylene a matsi mai ƙasa sosai, ta yadda kowane ion ya yi karo sau ɗaya kawai a mafi yawa, kuma suka ƙidaya abubuwan da aka samar da mass spectrometers, a kuzarin karo daga electronvolt 0.1 zuwa 10. Lissafin quantum chemistry da wani ingantaccen samfuri na yadda abokan biyu ke jan juna sun cika hoton.

Abu ɗaya ya fi rinjaye

A ƙaramin kuzari:

• kashi 99% na martanin suna samar da ion HCCP⁺ tare da atom na hydrogen;
• kashi 1% suna samar da CCP⁺ tare da ƙwayar hydrogen — sau goma fiye da abin da lissafin 2012 ya yi hasashe.

Hanyar CCP⁺ bai kamata ma ta kasance a buɗe ba ga ion da ke cikin yanayinsu na “spin” na maganaɗisu da aka saba. Kasancewarta tana nuna cewa abokan karo biyun na iya juya spin ɗinsu yayin haɗuwa, wani tsari da ake kira intersystem crossing. Marubutan sun bayyana shi da haɗakar da ba ta da ƙarfi da ke daɗewa har jujjuyawar ta faru — musamman a ƙaramin kuzari.

Abu na uku da aka ruwaito a 1989–1990, wani ƙwaya da aka haɗa, bai taɓa bayyana ba. Ƙungiyar ta danganta shi ga matsi mafi girma na tsohuwar dabara, kuma ba ta tsammaninsa a sararin samaniya.

Mafi sauri a sanyi

Ta mayar da ma’aunansu zuwa saurin martani daga kelvin 10 zuwa 5,000, sun sami 1.1 × 10⁻⁹ cm³ a daƙiƙa a zafin ɗaki — kusa da tsohuwar ƙima — amma sauri da ke ƙaruwa yayin da zafi ke raguwa, ya kai 1.3 × 10⁻⁹ a kelvin 10, maimakon ƙimar da ba ta canzawa da aka yi amfani da ita har yanzu. Dalilin: rarrabuwar cajin lantarki mai tsawo ta acetylene tana jan ion da ƙarfi fiye da yadda daidaitaccen samfuri ke zato. Sun ba da dabarun lissafi da ke shirye a saka su cikin rumbun bayanan astrochemistry.

A kewayen wani tsohon tauraron carbon

Ƙungiyar ta ƙara martanin cikin samfurin sinadarai na IRC +10216, wani tsoho tauraro mai yawan carbon, wanda ke kewaye da lulluɓi inda aka gano ƙwayoyin phosphorus da dama. Ion na phosphorus suna zama mafi yawa a cikin layukan waje, acetylene kuma a cikin na ciki, amma suna haɗuwa a kusan santimita 3 × 10¹⁶ daga tauraron. A can, martanin ya zama babbar ƙofar ion masu ɗauke da phosphorus da kuma babban tushen HCCP⁺. A cikin gajimaren tsakanin taurari, HCCP⁺ da ya kama electron zai iya samar da CP da CCP — biyu daga cikin ƙwayoyin sinadarai uku da aka riga aka gani.

Samfurin ya yi hasashen HCCP⁺ da CCP⁺ a yawa masu kama da juna. Duba wannan zai buƙaci na’urorin hangen nesa su same su — kuma, da farko, ma’aunan ɗakin gwaji na alamominsu na rediyo, waɗanda, gwargwadon sanin marubutan, ba a taɓa yi ba.