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ÀÍÒÈÔÅÐÐÎÌÀÃÍÅÒÈÊ |
| Áîëüøàÿ ñîâåòñêàÿ ýíöèêëîïåäèÿ (ÁÝÑ) |
âåùåñòâî, â êîòîðîì óñòàíîâèëñÿ àíòèôåððîìàãíèòíûé ïîðÿäîê ìàãíèòíûõ ìîìåíòîâ àòîìîâ èëè èîíîâ (ñì. Àíòèôåððîìàãíåòèçì). Îáû÷íî âåùåñòâî ñòàíîâèòñÿ À. íèæå îïðåäåë¸ííîé òåìïåðàòóðû TN (ñì. Íååëÿ òî÷êà) è îñòà¸òñÿ À. âïëîòü äî Ò = 0 Ê. Ñðåäè ýëåìåíòîâ À. ÿâëÿþòñÿ òâ¸ðäûé êèñëîðîä (-ìîäèôèêàöèÿ ïðè Ò < 24 Ê), õðîì (TN = 310 Ê), à òàêæå ðÿä ðåäêîçåìåëüíûõ ìåòàëëîâ.  ïîñëåäíèõ îáû÷íî íàáëþäàþòñÿ ñëîæíûå àíòèôåððîìàãíèòíûå ñòðóêòóðû â òåìïåðàòóðíîé îáëàñòè ìåæäó TN è (OK < T1 < TN). Ïðè áîëåå íèçêèõ òåìïåðàòóðàõ îíè ñòàíîâÿòñÿ ôåððîìàãíåòèêàìè (Ñì. Ôåððîìàãíåòèêè). Äàííûå î íàèáîëåå èçâåñòíûõ À. — ðåäêèõ çåìëÿõ — ïðèâåäåíû â òàáëèöå 1.
Òàáëèöà 1.
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| Ýëåìåíò | T1, K | TN, K |
|-----------------------------------------------------------------------------|
| Dy | 85 | 179 |
|-----------------------------------------------------------------------------|
| Ho | 20 | 133 |
|-----------------------------------------------------------------------------|
| Er | 20 | 85 |
|-----------------------------------------------------------------------------|
| Tu | 22 | 60 |
|-----------------------------------------------------------------------------|
| Tb | 219 | 230 |
------------------------------------------------------------------------------
Òàáëèöà 2.
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| Ñîåäèíåíèå | TN, K |
|------------------------------------------------|
| MnO | 120 |
|------------------------------------------------|
| FeO | 190 |
|------------------------------------------------|
| CoO | 290 |
|------------------------------------------------|
| NiO | 650 |
|------------------------------------------------|
| MnF2 | 72 |
|------------------------------------------------|
| FeF2 | 250 |
|------------------------------------------------|
| CoF2 | 37,7 |
|------------------------------------------------|
| NiF2 | 73,2 |
|------------------------------------------------|
| MnSO4 | 12 |
|------------------------------------------------|
| FeSO4 | 21 |
|------------------------------------------------|
| CoSO4 | 12 |
|------------------------------------------------|
| NiSO4 | 37 |
|------------------------------------------------|
| MnCO3 | 32,5 |
|------------------------------------------------|
| FeCO3 | 35 |
|------------------------------------------------|
| CoCO3 | 38 |
|------------------------------------------------|
| NiCO3 | 25 |
--------------------------------------------------
×èñëî èçâåñòíûõ õèìè÷åñêèõ ñîåäèíåíèé, êîòîðûå ñòàíîâÿòñÿ À. ïðè îïðåäåë¸ííûõ òåìïåðàòóðàõ, ïðèáëèæàåòñÿ ê òûñÿ÷å. Ðÿä íàèáîëåå ïðîñòûõ À. è èõ òåìïåðàòóðû TN ïðèâåäåíû â òàáë. 2.
Áîëüøàÿ ÷àñòü À. îáëàäàåò çíà÷åíèÿìè TN, ëåæàùèìè ñóùåñòâåííî íèæå êîìíàòíîé òåìïåðàòóðû. Äëÿ âñåõ ãèäðàòèðîâàííûõ ñîëåé TN íå ïðåâûøàåò 10 Ê, íàïðèìåð TN = 4,31 Ê ó CuCl2·2H2O.
Ëèò.: ñì. ïðè ñò. Àíòèôåððîìàãíåòèçì.
À. Ñ. Áîðîâèê-Ðîìàíîâ.
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| Îðôîãðàôè÷åñêèé ñëîâàðü Ëîïàòèíà |
| àíòèôåððîìàãí`åòèê, àíòèôåððîìàãí`åòèê, -à |
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