Unbitrium

This article is about an undiscovered element. Once it is discovered, this article will be edited with more information.

Unbitrium
Symbol	Ubt
Number	123
Group, Period	between 2 and 3, 8
Mass number	not applicable
Category	Superactinide
Electronic properties
Electrons per shell	2,8,18,32,32,18,8,4 (Predicted)
Discovery information
Discoverer	Undiscovered
Date discovered	Undiscovered
Location discovered	Undiscovered

Unbitrium, Ubt, is the temporary name for element 123. Isotopes are predicted between the dripline and ³⁴⁴Ubt; between ³²²Ubt and ³¹⁸Ubt; and between ³¹⁶Ubt and ²⁸⁶Ubt. All of them have half-lives less than 1 day, and most are under 1 sec. ³⁵⁰Ubt may persist up to 2 hours after an event which led to its formation. All other isotopes will vanish in less than 1000 sec.

The ground state electron configuration of Ubt is uncertain, and may even be a superposition of two different configurations.

Ubt has the lowest atomic number of any element physicists have not attempted to synthesize.

NUCLEAR PROPERTIES

INFORMATION SOURCES

There has been considerable study of the decay properties of Ubt. Most of these have been limited to N < 220, but I know of only one which which reports decay properties of Ubt to the neutron dripline⁽¹⁾. Maps on pp 15 & 18 address the entire (Z,N) region covered, but report only the dominant decay mode and report half-lives only to within a band three orders of magnitude wide (0.001 - 1 sec, for example). More detailed estimates of these properties can be extracted from maps on pp 11 & 12, but only for a limited range of Z and N. Half-life data are reported by colors, which makes numerical estimates laborious to produce. Ref. 1 will be used as the primary reference in this article. Predictions from other sources will be compared to it.

An independent map of half-lives and decay modes exists⁽²⁾. The map shows a stabilized region in a band apparently ending near Z = 132. That band ends at Z = 118. Neutron counts in the region lie between N = 191 and N = 202, but the most stabilized nuclides lie in a band 195 <= N <= 200. Ref. 1 does not show this region.

An interactive site exists which has tables of b-, b+, and alpha decay(1) half-lives for Z up to 135 and A up to 339⁽³⁾. Total half-lives and branch ratios can be computed from these to provide a third pair of maps. This model does not show particular stabilization around N = 200, aligning with Ref. 1 in this regard.

PREDICTED PROPERTIES

Even-N isotopes from the neutron dripline down to ³⁹⁸Ubt decay predominantly by beta emission with half-lives in the 0.001 - 1 sec range. Half-lives aren't reported, but the properties of beta decay indicate that half-lives close to 0.001 sec are likely⁽³⁾. Odd-N drops in this band decay by neutron emission.

All isotopes in the band ³⁹⁷Ubt to ³⁷⁷Ubt are predicted to have half-lives in the 0.001 - 1 sec range. Beta emission is reported as the dominant decay mode of heavier isotopes in the band, while lighter isotopes have either beta emission or fission as dominant modes. It is likely that both modes are important in most isotopes.

Between ³⁷⁶Ubt and ³⁶⁷Ubt, decay modes and half-lives are complicated. Both fission and beta decay occur, and half-lives range from 10^-09 to 0.001 sec for fission decaying isotopes. Two beta-decaying isotopes, ³⁷⁵Ubt and ³⁷²Ubt, are predicted to have half-lives predicted to lie in the 0.001 - 1 sec range. Decay properties seem to be defined by N count, with the pattern extending across a range of Z values. It is likely that those properties are a result of the model, although they may be real.

Isotopes in the band ³⁶⁶Ubt to ³⁶⁴Ubt are all predicted to decay by fission, but with with half-lives in the range 0.001 - 1 sec.

Isotopes in the band ³⁶³Ubt to ³⁵²Ubt are predicted to decay by beta emission and have half-lives in the 0.001 - 1 sec range.

Isotopes in the band ³⁵¹Ubt to ³⁴⁶Ubt are predicted to decay by beta emission and have half-lives in the 1 - 1000 sec range. Note that neutron count for ³⁵¹Ubt is 228. A closer look at half-lives (p 12) indicates that none of them have half-lives exceeding a few seconds.

³⁴⁵Ubt to ³⁴²Ubt are predicted to decay by fission. Their half-lives decline rapidly as N decreases.

Ref 1 predicts a gap from ³⁴¹Ubt to ³¹⁷Ubt, which is predicted to be occupied by nuclear drops or very short-lived nuclides.

Ref, 2 reports isotopes with half-lives above 10^-06 sec in the band ³²²Ubt - ³¹⁸Ubt. Of these, ³²²Ubt to ³²⁰Ubt have half-lives in the 1 sec - 1 day band; and the other two have half-lives in the 0.001 - 1 sec band. Aside from these it predicts a wide band of isotopes predicted to decay by <10^-06 sec. These can't be compared with Ref. 1 due to the difference in half-life cutoff.

Ref 1 predicts ³¹⁶Ubt to ³¹⁴Ubt will decay by quickly and by fission.

It also predicts that ³¹³Ubt through ²⁹⁰Ubt should decay by alpha emission. Half-lives for most are short, but ³⁰⁷Ubt to ²⁹⁸Ubt are predicted to have half-lives in the 10^-06 - 0.001 sec range. (Note that neutron count for ³⁰⁷Ubt is 184.) Ref 2 predicts fission down as far as ³⁰⁶Ubt.

Finally, ²⁸⁹Ubt to ²⁸⁶Ubt are predicted to decay rapidly by proton emission.

OCCURRENCE

FORMATION

All even-N nuclear drops from the neutron dripline to ³⁹⁸Ubt are predicted to be nuclides. All nuclear drops in the bands ³⁹⁷Ubt to ³⁴²Ubt are predicted to be nuclides. Some of the heavier isotopes in that band can form directly as a neutron star disintegrates. Most of them however require a chain of beta decays to form. ³⁷³Ubt, ³⁷²Ubt, and ³⁶⁹Ubt to ³⁶⁷Ubt cannot form because their beta decay chains are interrupted by fission at lower Z. All the others down to ³⁴²Ubt can form. Ref 2 shows nuclides in the band from ³²²Ubt to ³¹⁸Ubt. Beta decay chains leading to them are all interrupted. None of them can form. Ref. 1 also predicts all drops in the band ³¹⁶Ubt to ²⁸⁶Ubt are nuclides. None of them can form. It is possible to simulate the formation of nuclides via beta decay chains using data from Ref. 3 and assuming an initial distribution close to the neutron dripline. Details of the model are provided in "Nuclear Decay Chains at High A" in this wiki. Per that model, at least 59 isotopes between ⁴⁰¹Ubt and ³⁴³Ubt can form.

Neutron capture may be able to produce nuclides up to A around 380 before fission attrition stops further growth. Neutron capture is expected to contribute to formation of all significant Ubt isotopes.

PERSISTENCE

³⁵¹Ubt and heavier isotopes will vanish within 1000 sec after a supernova or neutron star merger which led to their formation, or lie at higher Z than beta-decay chains which end in nuclides which fission with a half-life not much greater than 1 sec.

³⁵⁰Ubt through ³⁴⁷Ubt are not formed via alpha infall, but only beta decay chains from the dripline. None of these isotopes is expected to persist more than 3600 sec.

³⁴⁶Ubq and lighter isotopes all have nothing but short-lived precursors, or will lie at a Z beyond the point at which a short-lived beta decay chain terminates. All of those isotopes are expected to vanish within 1000 sec; they are not expected to persist a significant amount of time.

ATOMIC PROPERTIES

Ubt is expected to be an 8th period active metal (superactinide). Its electron configuration has been predicted⁽⁴⁾ to be [Og] 6f¹ 7d¹ 8s² 8p¹_1/2. However, at least one alternate configuration may be the ground state⁽⁵⁾. Its ground state may even be a superposition of two configurations.

REFERENCES

1. "Decay Modes and a Limit of Existence of Nuclei"; H. Koura; 4th Int. Conf. on the Chemistry and Physics of Transactinide Elements; Sept. 2011.

2. “Systematic Study of Decay Properties of Heaviest Elements.”; Y. M. Palenzuelaa, L. F. Ruiza, A. Karpov, and W. Greiner; Bulletin of the Russian Academy of Sciences, Physics.  Vol . 76, No.11, pp 1165 – 1177; 2012

3. "Nuclear Properties for Astrophysical Applications"; P. Moller & J. R. Nix; Los Alamos National Laboratory website; search by "LANL, T2", then "Nuclear Properties for Astrophysical Applications".

4. "Extended Periodic Table", Wikipedia

5. "Electronic structure of element 123"; Koen van der Schoor; Rijksuniversiteit Groningen Bachelor Research Project; 2016. (Accessible via Wikipedia's article "Extended Periodic Table".)

6. Other references are found in the wiki articles cited.

9-Period Periodic Table of Elements
1	1 H																																																																	2 He
2	3 Li	4 Be																																																																	5 B	6 C	7 N	8 O	9 F	10 Ne
3	11 Na	12 Mg																																																																	13 Al	14 Si	15 P	16 S	17 Cl	18 Ar
4	19 K	20 Ca																																																																	21 Sc	22 Ti	23 V	24 Cr	25 Mn	26 Fe	27 Co	28 Ni	29 Cu	30 Zn	31 Ga	32 Ge	33 As	34 Se	35 Br	36 Kr
5	37 Rb	38 Sr																																																																	39 Y	40 Zr	41 Nb	42 Mo	43 Tc	44 Ru	45 Rh	46 Pd	47 Ag	48 Cd	49 In	50 Sn	51 Sb	52 Te	53 I	54 Xe
6	55 Cs	56 Ba																																																					57 La	58 Ce	59 Pr	60 Nd	61 Pm	62 Sm	63 Eu	64 Gd	65 Tb	66 Dy	67 Ho	68 Er	69 Tm	70 Yb	71 Lu	72 Hf	73 Ta	74 W	75 Re	76 Os	77 Ir	78 Pt	79 Au	80 Hg	81 Tl	82 Pb	83 Bi	84 Po	85 At	86 Rn
7	87 Fr	88 Ra																																																					89 Ac	90 Th	91 Pa	92 U	93 Np	94 Pu	95 Am	96 Cm	97 Bk	98 Cf	99 Es	100 Fm	101 Md	102 No	103 Lr	104 Rf	105 Db	106 Sg	107 Bh	108 Hs	109 Mt	110 Ds	111 Rg	112 Cn	113 Nh	114 Fl	115 Mc	116 Lv	117 Ts	118 Og
8	119 Uue	120 Ubn																															121 Ubu	122 Ubb	123 Ubt	124 Ubq	125 Ubp	126 Ubh	127 Ubs	128 Ubo	129 Ube	130 Utn	131 Utu	132 Utb	133 Utt	134 Utq	135 Utp	136 Uth	137 Uts	138 Uto	139 Ute	140 Uqn	141 Uqu	142 Uqb	143 Uqt	144 Uqq	145 Uqp	146 Uqh	147 Uqs	148 Uqo	149 Uqe	150 Upn	151 Upu	152 Upb	153 Upt	154 Upq	155 Upp	156 Uph	157 Ups	158 Upo	159 Upe	160 Uhn	161 Uhu	162 Uhb	163 Uht	164 Uhq	165 Uhp	166 Uhh	167 Uhs	168 Uho	169 Uhe	170 Usn	171 Usu	172 Usb
9	173 Ust	174 Usq
Alkali metal Alkaline earth metal Lanthanide Actinide Superactinide Transition metal Post-transition metal Metalloid Other nonmetal Halogen Noble gas predicted predicted predicted predicted predicted predicted predicted predicted predicted

(09-15-20)