Inorganic imide explained

The inorganic imide is an inorganic chemical compound containing

• an anion with the chemical formula, in which nitrogen atom is covalently bonded to one hydrogen atom (as in lithium imide and calcium imide). The other name of that anion is monohydrogen nitride.
• functional groups with the chemical formulas or, in which nitrogen atom is also covalently bonded to one hydrogen atom, with two covalent single bonds or one covalent double bond from the nitrogen atom to other atoms, respectively (as in heptasulfur imide, sulfur diimide and nitroxyl).

Organic imides have the functional groups or as well.

The imides are related to the inorganic amides, containing the anions, the nitrides, containing the anions and the nitridohydrides or nitride hydrides, containing both nitride and hydride anions.

In addition to solid state imides, molecular imides are also known in dilute gases, where their spectrum can be studied.

When covalently bound to a metal, an imide ligand produces a transition metal imido complex.

When the hydrogen of the imide group is substituted by an organic group, an organoimide results. Complexes of actinide and rare earth elements with organoimides are known.^[1]

Properties

Lithium imide undergoes a phase transition at 87 °C where it goes from an ordered to a more symmetric disordered state.^[2]

Structure

Many imides have a cubic rock salt structure, with the metal and nitrogen occupying the main positions. The position of the hydrogen atom is hard to determine, but is disordered.

Many of the heavy metal simple imide molecules are linear. This is due to the filled 2p orbital of nitrogen donating electrons to an empty d orbital on the metal.^[3]

Formation

Heating lithium amide with lithium hydride yields lithium imide and hydrogen gas. This reaction takes place as released ammonia reacts with lithium hydride.

Heating magnesium amide to about 400 °C yields magnesium imide with the loss of ammonia. Magnesium imide itself decomposes if heated between 455 and 490 °C.

Beryllium imide forms from beryllium amide when heated to 230 °C in a vacuum.^[4]

When strontium metal is heated with ammonia at 750 °C, the dark yellow strontium imide forms.

When barium vapour is heated with ammonia in an electrical discharge, the gaseous, molecular BaNH is formed.^[5] Molecules ScNH, YNH, and LaNH are also known.^{[6] [7]}

Hydrogen storage

Inorganic imides are of interest because they can reversibly store hydrogen, which may be important for the hydrogen economy. For example, calcium imide can store 2.1% mass of hydrogen. reversibly stores hydrogen and release it at temperatures between 140 and 206 °C. It can reversibly hold 2.3% hydrogen.^[8] When hydrogen is added to the imide, amides and hydrides are produced. When imides are heated, they can yield hydridonitrides or nitrides, but these may not easily reabsorb hydrogen.

List

Ionic

name	formula	structure	space group	unit cell	references
Lithium imide		cubic	Fmm	a=5.0742
Beryllium imide	BeNH
Magnesium imide	MgNH	hexagonal	P6/m	a = 11.567 Å c = 3.683Å Z=12	^[9]
Dilithium magnesium imide
Disilicon dinitride imide					^[10]
		amourphous			^[11]
		amourphous
		amourphous
potassium imido nitrido silicate		cubic	P4332	a = 10.789
Calcium imide	CaNH	hexagonal	Fm3m
Dilithium calcium imide		hexagonal
Magnesium calcium diimide		cubic			^[12]
Lithium calcium magnesium imide
Strontium imide	SrNH	orthorhombic	Pmna	a =7.5770 b =3.92260 c =5.69652 Z=4	^[13]
Tin(IV) diamide imide					^[14] ^[15]
Barium imide	BaNH	tetragonal	I4/mmm	a=4.062 c=6.072 Z=2	^[16]
Lanthanum imide		rock salt		a=5.32	^[17]
Cerium(II) imide	CeNH				^[18]
Ytterbium(II) imide	YbNH	cubic		a=4.85
		cubic	P4132	a = 10.304, Z = 4	^[19]
Thorium(IV) dinitride imide		hexagonal	P3m	a = 3.886 c = 6.185 Å	^[20]

Molecular

name	formula	structure	symmetry	CAS	references
Boron imide		polymer			^[21]
	HNO	bent		14332-28-6
Aluminium amide imide		polymer
Silicon dimide
	HNS	bent		14616-59-2	^[22]
Sulfur diimide
Heptasulfur imide				293-42-5	^[23]
				1003-75-4
				1003-76-5
				638-50-6
Scandium(II) imide	ScNH
Gallium(III) imide		polymer
Yttrium(II) imide	YNH
Barium imide	BaNH	linear
Lanthanum(II) imide	LaNH	linear	C∞v		^[24]
Cerium(II) imide	CeNH	linear	C∞v
Uranimine nitride					^[25]
Uranimine dihydride

Molecular imines of other actinides called neptunimine and plutonimine have been postulated to exist in the gas phase or noble gas matrix.^[26]

Notes and References

1. Schädle . Dorothea . Anwander . Reiner . Rare-earth metal and actinide organoimide chemistry . Chemical Society Reviews . 2019 . 48 . 24 . 5752–5805 . 10.1039/c8cs00932e. 31720564 . 207938163.
2. Structural and thermogravimetric studies of alkali metal amides and imides. Oxford University, UK. 1999. PhD. en. Rebecca L.. Lowton.
3. Janczyk. Alexandra. Lichtenberger. Dennis L.. Ziurys. Lucy M.. Lucy Ziurys . February 2006. Competition between Metal-Amido and Metal-Imido Chemistries in the Alkaline Earth Series: An Experimental and Theoretical Study of BaNH. Journal of the American Chemical Society. en. 128. 4. 1109–1118. 10.1021/ja053473k. 16433526. 0002-7863.
4. Jacobs. Herbert. Juza. Robert. November 1969. Darstellung und Eigenschaften von Berylliumamid und -imid. Zeitschrift für anorganische und allgemeine Chemie. de. 370. 5–6. 248–253. 10.1002/zaac.19693700507. 0044-2313.
5. Janczyk . Alexandra . Lichtenberger . Dennis L. . Ziurys . Lucy M.. Lucy Ziurys . Competition between Metal-Amido and Metal-Imido Chemistries in the Alkaline Earth Series: An Experimental and Theoretical Study of BaNH . Journal of the American Chemical Society . February 2006 . 128 . 4 . 1109–1118 . 10.1021/ja053473k. 16433526.
6. Bhattacharyya . Soumen . Harrison . James F. . Electronic structure and bonding of the ScNH and YNH molecules . Chemical Physics Letters . September 2020 . 754 . 137735 . 10.1016/j.cplett.2020.137735. 2020CPL...75437735B . 225222419.
7. Bhattacharyya . Soumen . Harrison . J. F. . Theoretical study of the electronic structure and bonding of LaNH . Chemical Physics Letters . 1 September 2019 . 730 . 551–556 . 10.1016/j.cplett.2019.06.042. 2019CPL...730..551B . 197120516.
8. Verbraeken . Maarten Christiaan . Doped Alkaline Earth (nitride) Hydrides . February 2009 . University of St Andrews . 19. 10023/714.
9. Dolci . Francesco . Napolitano . Emilio . Weidner . Eveline . Enzo . Stefano . Moretto . Pietro . Brunelli . Michela . Hansen . Thomas . Fichtner . Maximilian . Lohstroh . Wiebke . Magnesium Imide: Synthesis and Structure Determination of an Unconventional Alkaline Earth Imide from Decomposition of Magnesium Amide . Inorganic Chemistry . 7 February 2011 . 50 . 3 . 1116–1122 . 10.1021/ic1023778. 21190329 .
10. Peters. D.. Paulus. E. F.. Jacobs. H.. 1990. Darstellung und Kristallstruktur eines Kaliumimidonitridosilicats, K3Si6N5(NH)6. Zeitschrift für anorganische und allgemeine Chemie. de. 584. 1. 129–137. 10.1002/zaac.19905840112. 0044-2313.
11. Ali. S. I.. December 1970. Reactions of Silicon Tetrabromide and -iodide with Potassium Amide in liquid ammonia. Zeitschrift für anorganische und allgemeine Chemie. de. 379. 1. 68–71. 10.1002/zaac.19703790112. 0044-2313.
12. Liu . Yongfeng . Liu . Tao . Xiong . Zhitao . Hu . Jianjiang . Wu . Guotao . Chen . Ping . Wee . Andrew T. S. . Yang . Ping . Murata . Kenji . Sakata . Ko . Synthesis and Structural Characterization of a New Alkaline Earth Imide: MgCa(NH)2 . European Journal of Inorganic Chemistry . November 2006 . 2006 . 21 . 4368–4373 . 10.1002/ejic.200600492. free.
13. Schultz‐Coulon . Verena . Irran . Elisabeth . Putz . Bernd . Schnick . Wolfgang . β-SrNH und β-SrND – Synthese und Kristallstrukturbestimmung mittels Röntgen- und Neutronenbeugung an Pulvern . Zeitschrift für anorganische und allgemeine Chemie . 1999 . 625 . 7 . 1086–1092 . 10.1002/(SICI)1521-3749(199907)625:7<1086::AID-ZAAC1086>3.0.CO;2-B.
14. Watney. Nicholas S. P.. Gál. Zoltán A.. Webster. Matthew D. S.. Clarke. Simon J.. 2005. The first ternary tin(ii) nitride: NaSnN. Chemical Communications. en. 33. 4190–2. 10.1039/b505208d. 16100599. 1359-7345.
15. Maya. Leon. May 1992. Preparation of tin nitride via an amide-imide intermediate. Inorganic Chemistry. en. 31. 10. 1958–1960. 10.1021/ic00036a044. 0020-1669.
16. Wegner . B. . Essmann . R. . Jacobs . H. . Fischer . P. . Synthesis of barium imide from the elements and orientational disorder of anions in BaND studied by neutron diffraction from 8 to 294 K . Journal of the Less Common Metals . December 1990 . 167 . 1 . 81–90 . 10.1016/0022-5088(90)90291-Q . en.
17. Jacobs. H. Gieger. B. Hadenfeldt. C. March 1979. Über das system kalium/lanthan/ammoniak. Journal of the Less Common Metals. de. 64. 1. 91–99. 10.1016/0022-5088(79)90136-X.
18. Imamura. Hayao. Kawasoe. Masahiro. Imayoshi. Kyouya. Sakata. Yoshihisa. 2015. Preparation and Some Properties of Nanostructural Rare Earth Nitrides by Using the Reaction of Hydrides with Ammonia. International Journal of Theoretical and Applied Nanotechnology. 3. 1–8. 10.11159/ijtan.2015.001. free.
19. Bildung von NH4[Hg3(NH)2](NO3)3 und Umwandlung in [Hg2N](NO3). Zeitschrift für Anorganische und Allgemeine Chemie. 2002. 10.1002/1521-3749(200212)628:12<2709::AID-ZAAC2709>3.0.CO;2-P. Nockemann. Peter. Meyer. Gerd. 628. 12. 2709–2714.
20. Silva. G. W. Chinthaka. Yeamans. Charles B.. Weck. Philppe F.. Hunn. John D.. Cerefice. Gary S.. Sattelberger. Alfred P.. Czerwinski. Ken R.. 2012-03-05. Synthesis and Characterization of Th 2 N 2 (NH) Isomorphous to Th 2 N 3. Inorganic Chemistry. en. 51. 5. 3332–3340. 10.1021/ic300025b. 22360445. 0020-1669.
21. Janik. Jerzy F.. Wells. Richard L.. January 1996. Gallium Imide, n, a New Polymeric Precursor for Gallium Nitride Powders. Chemistry of Materials. en. 8. 12. 2708–2711. 10.1021/cm960419h. 0897-4756.
22. Nguyen. Minh Tho. Vanquickenborne. L.G.. Plisnier. Michel. Flammang. Robert. January 1993. A mass spectrometric and ab initio molecular orbital characterization of thionitrosyl hydride (H-N=S). Molecular Physics. en. 78. 1. 111–119. 10.1080/00268979300100111. 1993MolPh..78..111N. 0026-8976.
23. Mendelsohn . M.H. . Jolly . W.L. . Reactions of the heptasulfur imide anion . Journal of Inorganic and Nuclear Chemistry . January 1973 . 35 . 1 . 95–99 . 10.1016/0022-1902(73)80614-1. 98171750 .
24. Zhang. Yuchen. Nyambo. Silver. Yang. Dong-Sheng. 2018-12-21. Mass-analyzed threshold ionization spectroscopy of lanthanide imide LnNH (Ln = La and Ce) radicals from N–H bond activation of ammonia. The Journal of Chemical Physics. en. 149. 23. 234301. 10.1063/1.5064597. 30579310. 2018JChPh.149w4301Z. 58639516. 0021-9606.
25. Wang. Xuefeng. Andrews. Lester. Vlaisavljevich. Bess. Gagliardi. Laura. 2011-04-18. Combined Triple and Double Bonds to Uranium: The N≡U═N−H Uranimine Nitride Molecule Prepared in Solid Argon. Inorganic Chemistry. en. 50. 8. 3826–3831. 10.1021/ic2003244. 21405096. 0020-1669.
26. Li. Peng. Niu. Wenxia. Gao. Tao. 2015-11-25. Systematic analysis of structural and spectroscopic properties of neptunimine (HN=NpH2) and plutonimine (HN=PuH2). Journal of Molecular Modeling. en. 21. 12. 316. 10.1007/s00894-015-2856-1. 26608606. 7587370. 0948-5023.