We have isotopes in tpt, but no ions.  Well here are 6 ideas for elements that simulate ions as well as a new property for DSTW:

Negative ions (or NION):

NION is a blue gas.  Brush-spawned NION has a life value of 60 that goes down by 1 every frame.  When the life value of one pixel of NION reaches 0, it splits into 2 NIONs each with a life value of 60.  If inside a container with no empty space, then instead of spliting into 2 of itself, it generates a pressure of 5 instead.  This pressure doesn't go down until empty space becomes available; this mean that pressure generated in this way adds up by 5 every 60 frames and is lowered when empty space opens up, making NION difficult to contain.  NION turns into NSIN (see below) at -30C and into NICH (see below) at 500C.  It sparks conductive elements but is not an ideal power source given the fact that the pressure it generates can break any element that is sensitive to pressure, such as WIFI, BMTL, etc.

Solid negative ions (or NSIN):

NSIN is a blue solid.  Unlike NION (see above) it's more stable and doesn't make more of itself in any situation; this makes it much easier to contain.  It never turns back into it's gaseous counterpart except by console, property tool, or CONV.  It can function as a rechargeable battery; it absorbs electrons and it's life value increases by 1 for every electron it absorbs.  When it's life value is non-zero, it sparks any conductve element it comes into contact with and it's life value goes down by 1 for every SPRK it emits.  It's maximum life value is 100, any higher than that and it turns into NICH (see below).  NSIN also turns into NICH when it reaches a temperature of 500C, the same temperature at which NION turns into NICH.  NSIN doesn't turn back into NION in any way except by console, property tool, or CONV.

Negative ionic charges (or NICH):

NICH is a blue energy particle.  As mentioned above NION (see above) and NSIN (see above) both turn into it at a temperature of 500C.  It does not turn back into either of the aformentioned elements in any way except by console, property tool, or CONV.  It sparks electically conductive elements the same way electrons do.  If a NICH pixel comes into contact with a neutron, the particles fuse together into PLSM (not realistic, but neither is neutrons and electrons fusing into HYGN).

Positive ions (or PION):

PION is a red gas.  It has all the same properties as NION (see above) except that it removes sparks instead of generating them, turns into PSIN (see below) at -30C, and turns into PICH (see below) at 500C.

Solid positive ions (or PSIN):

PSIN is a red solid.  Like NSIN (see above) and unlike NION (see above) or PION (see above), It doesn't duplicate itself; like NSIN, it never turns back into it's gaseous counterpart except by console, property tool, or CONV, and like all the aformentioned elements, it turns into it's enegy particle counterpart at 500C.  It absorbs protons and it's life value goes up by 1 for every proton it absorbs.  If it's life value is non-zero, it absorbs SPRK and it's life value goes down by 1 for every SPRK it absorbs.  You might think that this feature is useless because it just makes PSIN a temporary alternative to INSL, but there's a trick you can do with it and DRAY.  If you use DRAY/PSCN to constantly make copies of a PSIN pixel with a certain life value, you can reduce the number of SPRKs that pass through a wire.  For example, you could use DRAY/PSCN to copy a PSIN with a life value of 1 and the copy will only let every other SPRK pass though in a wire; a DRAY/PSCN-made copy of PSIN with a life value of 2 will only let every 3rd SPRK pass through and so on.  The maximum life value is 100, any higher than that and it turns into PICH (see below).  A DRAY/PSCN-made copy of PSIN with a life value of 100 will stop all SPRKs form passin though a wire.  This; however, is pointless as INSL can do this with fewer parts; it's recommended to just use INSL for that one.

Positive ionic charges (or PICH):

PICH is a red energy particle.  It look identical to protons in nothing display but in fire display, it glows a different kind of red than protons do; whereas protons glow rose red, PICH glows true red.  Like NICH (see above), it can't turn back into it's gaseous or solid counterparts by any means except by console, property tool, or CONV.  It removes SPRKs the same way protons do.  If a PICH pixel comes into contact with an electron, the particles fuse together into PLSM (now THAT'S realistic).

Shared prperties:

NION, NSIN, and NICH all turn WATR, BUBW, or SLTW into DSTW.  They don't do this with FRZW or DSTW (obviously).  NION is absorbed by WATR, BUBW, and SLTW which turn them into DSTW, and NICH is absorbed by the afformentioned water variants because it sparks them in addition to turning them into DSTW, but NSIN is unaffected by all water variants.  NION, NSIN, and NICH are all immune to virus (solid, liquid, or gas) and, like SOAP, they all either kill or cure it.  They also all absorb DUST, SMKE, or CO2, this simulates real life ambient negative ions removing pollutants from the air.  PION, PSIN, and PICH are all immune to virus (solid, liquid, or gas) and while PION and PSIN don't affect it, PICH makes it undying (but curable) the same way protons do.  Not only that, but PICH make virus (solid, liquid, or gas) grow and the resulting virus is also undying (but curable); remember PICH, like all the suggested elements in this thread, can't be infected by virus (solid, liquid, or gas), so the the virus in this situation is growing without infecting anything.  All of the suggested elements in this thread also become LITH when they come into contact with their opposites, but they do so in different ways; if NION and PION come into contact, they fuse together and become one pixel of uncharged LITH; if NSIN and PSIN come into contact, each one of them becomes a pixel of uncharged LITH like CLST and NITR both become TNT upon contact with each other;  if NICH and PICH come into contact, each one of them become a pixel of fully charged LITH, also like CLST and NITR both become TNT upon contact with each other.  The last latter reaction is a perfect way to make fully charged rechargeable battery factories.

New property for DSTW:

DSTW can now be sparked, but only by NION, NSIN, or NICH.  This make sense, since they're supposed to turn WATR, BUBW, and SLTW into DSTW, but they're also supposed to spark the aformentioned water variants due to the fact that the aformentioned water variants are all electrically conductive.

EDIT:  A comment by xCreeperBombx below has brought to my attention that NION and PION have the potential to cause lag; I have decided to take his advice and make it so NION and PION's life and tmp values double with every split but only the life value counts down.

@username90000 (View Post)

For one thing, with these elements we have a reaction that makes LITH.

Who said that protons have to be the only element that deletes SPRKs?  And there is curently no way to produce LITH via reactions.  Plus, there are plenty of properties unique to all these elements.

@xCreeperBombx (View Post)

 Good idea; I shall append it to the suggestion above.