Table 1. Overview of the structural transitions of transition-metal pnictide (TPn) compounds exhibiting the MnP-type structure.

The reference shorthands are explained below the table. FM indicates ferromagnetic order; ∥c indicates ferromagnetically ordered spins oriented along the c axis; HM indicates helimagnetic order; ↑c indicates helimagnetic propagation vector along the c axis; FS indicates full structure; UC indicates unit-cell parameters; TE indicates thermal expansion. Reference 9 is in parentheses to indicte it is relevant but does not directly give actual data.

		Transition
TPn	Magnetic order	Order	Structure (cooling)	Temperature	Hysteresis	Pressure	Available structural data	Superconductivity
CrP	No[1]	Second[1]	(NiAs→MnP)[1]	[>1350 (50) K][1]	–	Ambient	FS: 1.2 K, 4.2 K, 293 K[1] 17 K, 81 K, 293 K[2] 293 K[3–6]	–
							UC: 4–1200 K[7]
MnP	FM (∥c)[8]	Second[9]	MnP→MnP[10]	291.5 (2) K[11]	–	Ambient (suppressed by p)	FS: 10 K, 60 K, 293 K[10] 293[3,13,14] 0–40 GPa[15]	Yes (p-induced) p c ≃ 7.8 GPa, T c ≤ 1 K[19]
	HM (↑c)[8] (Complex magnetic p-T-H-diagram)	First[9]	MnP→MnP*[10] *No crossing of c/b = {\surd 3}	47 K	0.24 K[9]	Ambient (suppressed at p ≃ 1.4 GPa)	UC: 300–1300 K[16]0.5–7 GPa[17] TE: 4–80 K[18,(9)]
FeP	HM (↑c)[20]	(Second)[21]	MnP→MnP[21]	125 (1) K[20]	–	Ambient	FS: 293 K[3,20,22] 30–300 K[21]	–
							UC: 30–1300 K[16] 0–16 GPa[23]
							TE: 100–293 K[24]
CoP	No[16,25]						FS: 293 K[3]	–
							UC: 300–1300 K[7]
VAs	No[26]						FS: 293 K[26,27]	–
							UC: 4–1200 K[7]
CrAs	HM (↑c)[28]	Second[7]	NiAs→MnP[7]	1170 (20) K[7]	–	Ambient	FS: 90 K, 285 K[29] 80 K, 285 K[32] 90 K, 295 K[33] 1.5 K, 80 K, 300 K[34] (1.5–290 K)   @ 0–0.94 GPa[35]	Yes (p-induced) p c ≃ 0.4 GPa, T c ≤ 2.2 K[37]
		First[29]	MnP→MnP[30]	267 K[31]	7 K[31]	Ambient (suppressed at p ≃ 0.8 GPa)	UC: 90–320 K[30] 90–300 K[36] 100–1300 K[7]
MnAs	FM[38] (Complex magnetic p-T-H-diagram)	Second[38]	NiAs→MnP[38]	394 K[38]	–	Ambient (suppressed by p)	FS: 293 K[39, 40] 328 K[41] 284 K, 317 K[42] 4.2 K, 298 K[43] (15 K, 295 K)   @ 3.8 GPa[44]	–
		First[38]	MnP→NiAs[38]	306 K[38]	11 K[38]	Ambient (suppressed by p)	UC: 100–500 K[45]
FeAs	HM (↑c)[46]	(Second)[46]	MnP→MnP[46]	77 (1) K[46]	–	Ambient	FS: 12–293 K[46] 293 K[47] 0–8.3 GPa[48]	–
							UC: 12–1325 K[46]
CoAs	No[49]	Second[7]	NiAs→MnP[50]	1225 K[50]	–	Ambient	FS: 293 K[49] 0–4.9 GPa[48]	–
							UC: 4–1200 K[7]

References: [1] Selte et al. (1975 ▸); [2] Selte et al. (1972b ▸); [3] Rundqvist & Nawapong (1965 ▸); [4] Schönberg (1954 ▸); [5] Boller & Nowotny (1965 ▸); [6] Nowotny & Henglein (1938 ▸); [7] Selte & Kjekshus (1973a ▸); [8] Wang et al. (2016 ▸); [9] Shapira et al. (1981 ▸); [10] Fjellvåg & Kjekshus (1984 ▸); [11] Huber & Ridgley (1964 ▸); [12] Komatsubara et al. (1970 ▸); [13] Fjellvåg & Kjekshus (1986 ▸); [14] Zhigadlo et al. (2017 ▸); [15] Han et al. (2018 ▸); [16] Selte et al. (1978 ▸); [17] Yano et al. (2018 ▸); [18] Okamoto et al. (1968 ▸); [19] Cheng et al. (2015 ▸); [20] Felcher et al. (1971 ▸); [21] Chernyavskii et al. (2020 ▸); [22] Selte & Kjekshus (1972 ▸); [23] Gu et al. (2011 ▸); [24] Westerstrandh et al. (1977 ▸); [25] Motizuki et al. (2009 ▸); [26] Selte et al. (1972c ▸); [27] Bachmayer & Nowotny (1955 ▸); [28] Watanabe et al. (1969 ▸); [29] Boller & Kallel (1971 ▸); [30] Suzuki & Ido (1991 ▸); [31] Wu et al. (2010 ▸); [32] Selte et al. (1971 ▸); [33] Sen et al. (2019 ▸); [34] Keller et al. (2015 ▸); [35] Shen et al. (2016 ▸); [36] Kanaya et al. (2004 ▸); [37] Wu et al. (2014 ▸); [38] Zięba et al. (1982 ▸); [39] Nowotny et al. (1951 ▸); [40] Yuzuri & Yamada (1960 ▸); [41] Wilson & Kasper (1964 ▸); [42] Suzuki (1978 ▸); [43] Zięba et al. (1978 ▸); [44] Glazkov et al. (2003 ▸); [45] Suzuki & Ido (1982 ▸); [46] Selte et al. (1972a ▸); [47] Selte & Kjekshus (1969 ▸); [48] Lyman & Prewitt (1984 ▸); [49] Selte & Kjekshus (1971 ▸); [50] Heyding & Calvert (1957 ▸).